Dictionaries give different definitions. YourDictionary
at scale: on a large scale: involving large amounts or volumes of something
and Wiktionary
at scale [prepositional phrase]
On a large scale: involving large amounts or volumes of something.
- This manufacturing process is fine for a cottage industry, but it can't be done at scale.
give a purely (large-!) size-related definition.
LawInsider [amended slightly]
[Proven] at scale means that the proof needs to involve more than a lab test, a
pilot, or a single small region. It means that recycling of a certain
packaging type needs to be proven to work in practice in multiple
regions, collectively representing a significant geographical area in
terms of population size, ideally across different country and city
archetypes. This to indicate that the recycling in practice is
replicable, and that the design of the packaging is not the barrier to
realise recycling in practice in other countries.
gives a corresponding meaning, 'across the board / in all contexts / not niche'
while The Computer Language Company Inc. (courtesy of the Free Dictionary)
at scale A phrase that means at the required size to solve the problem. At scale typically refers to handling larger volumes.
and Martin Lassen at GrammarHow
'At scale' is an expression that implies that something has the
needed requirements to handle a task or problem. It has to do with
something or someone being good enough to tackle an issue. It is
mostly used when speaking technically.
give a required-size–related definition (the Computer Language Company definition with the caveat that this usually means using larger volumes).