...at some points it seems like they simplify what causes people and animals to act the way they do to that of robots/computers.
Among researchers and academics, the term reductionism is often used to mean mechanical explanations of complex things (sometimes alongside "mechanistic"); while it's uncontroversial in physics and chemistry, in psychology, philosophy and social sciences it is a term often used by researchers when criticising overly mechanical and simplistic computational or "input-output" based explanations of animal and human behaviour.
Quick example (this is a snippet from a longer quote below):
a weakness of the cognitive approach [to psychology]'s reliance on the computer analogy leads to a reductionist and mechanistic description of experiences and behaviour
Wikipedia's choice of illustration for their article is also rather perfect:
...and they describe it as:
In the sciences, application of methodological reductionism attempts explanation of entire systems in terms of their individual, constituent parts and their interactions
Reductionism exists in all sciences; in physics, chemistry, etc it is pretty uncontroversial, and is generally considered a positive, standard practice. For example, Richard Dawkins coined the term "hierarchical reductionism" for the view that there's a hierarchy of levels of detail for explaining everything, similar to the popular view that every science can ultimately be explained by the next science down: psychology by biology, biology by chemistry, and ultimately, everything by physics (see also XKCD's satirical take on this):
When you reach psychology, animal behaviour, social sciences and philosophy, however, it starts to become not uncommon to see reductionism used as a dirty word for the over-simplification of complex systems and behaviour to un-nuanced computer-like explanations. Greedy reductionism has been coined as a term for cases where researchers leap to overly simplistic mechanistic explanations of too-complex phenomena too easily, shallow reductionism is another similar term; and it's not hard to find examples of reductionism being talked about as something people studying the behaviour of animals and humans are accused of.
From Instrumental Biology published by University of Chicago Press:
From the philosophical reception of... [genetics] ...in the early sixties until the age of genetic engineering, reductionism was gospel. Now, like 'positivism', it is a term of derision and abuse for a doctrine widely repudiated in the philosophy of biology.
Here's a good example of the term being used by researchers in the context of animal behaviour research as a term for (overly?) mechanistic/robotic explanations in this paper:
Novartis Found Symp. 1998;213:176-86; discussion 186-92, 218-21.
What is wrong with reductionist explanations of behaviour?
Methodological reductionism has served biology well, but its problems in the study of behaviour include turning open systems into closed ones... I will exemplify these problems in the context of the study of behaviour. But the worst problem arises when reductionism becomes an ideology, especially in the context of human behaviour, when it makes the claims to explain complex social phenomena (e.g. violence, alcoholism, the gender division of labour or sexual orientation) in terms of disordered molecular biology or genes. In doing so, ideological reductionism manifests a cascade of errors in method and logic: reification, arbitrary agglomeration, improper quantification, confusion of statistical artefact with biological reality, spurious localization and misplaced causality.
You'll seldom catch a self-respecting researcher using terms like "robotic" in a serious article, but that's not far from what they're getting at here. Here's one example from an introduction to cognitive psychology (my bold, also, I fixed a typo...):
Cognitive psychology has been influenced by developments in computer science and analogies are often made between how a computer works and how we process information. Based on this computer analogy cognitive psychology is interested in how the brain inputs, stores and outputs information...
...It has been argued that a weakness of the cognitive approach's reliance on the computer analogy leads to a reductionist and mechanistic description of experiences and behaviour. Reductionism is the idea that complex phenomena can be explained by simpler things. The cognitive approach often takes this narrow focus and ignores social and emotional factors which may impact on cognition. For example, the autism study investigated just one central cognitive deficit as an explanation for autism. However the reductionist approach does have strengths. An advantage of the reductionist view is that by breaking down a phenomenon to its constituent parts it may be possible to understand the whole. This type of single mindedness has lead to some great discoveries in psychology as it has in the 'natural' sciences.
Here's another example, using "shallow" to distinguish good reductionism from bad:
Shallow Reductionism and the Problem of Complexity in Psychology
In his recent book The Mind Doesn't Work That Way, Fodor argues that computational modeling of global cognitive processes, such as abductive everyday reasoning, has not been successful. In this article the problem is analyzed in the framework of algorithmic information theory. It is argued that the failed approaches are characterized by shallow reductionism, which is rejected in favor of deep reductionism and nonreductionism.
If you're writing in an academic context, "reductionism" is a common term. If your sample sentence was in such a context, you might expect to see it worded like:
When he simplified individuals into the mechanical parts of a universal system, Bucky seemed guilty of a form of shallow reductionism
In a more lay context, you might use:
When he simplified individuals into the mechanical parts of a universal system, Bucky's view of people seemed too mechanistic
Most actual discussions of Bucky and reductionism I can find actually praise him for being less reductionist than his peers, in that his notion of synergy acknowledges that there are properties of complex systems that are not best measured as simply the accumulation of their parts. However, here's one example of a contemporary review describing him as reductionist:
What Fuller is engaged in is essentially a reductionism in which the basis of reality is events which are geometrical in nature. There are no things, no nouns of material substance. Synergetics gives us "the ability to identify all experience in terms of only angle and frequency"