A question on ELU asked for A word for making an event more likely or less likely and I proposed the verb pair favor/disfavor in an answer, with these examples:
For example, in the case of the Ising model, if we consider two neighboring variables, X, Y, the local function will favor (higher probabilities) configurations in which X = Y and will disfavor (lower probabilities) configurations in which X ≠ Y. Luis Sucar; Probabilistic Graphical Models (2020)
The universe does not carry a memory of past results that will favor or disfavor future outcomes. S. Martinez-Conde et al.; Sleights of Mind (2011)
There is no problem finding a dictionary definition for this sense of the verb favor:
Work to the advantage of.
Natural selection has favored bats Lexico
Of a circumstance, fact, etc.: To lend confirmation or support to (a belief, doctrine, rarely, a person); to point in the direction of.
1887 C. C. Abbott Waste-land Wanderings ii. 22 Every indication favored rain. (OED)
However, I was surprised when I couldn't find an opposite definition for the verb disfavor, such as work to the disadvantage of or weaken confirmation or support. For example, the sole definitions in these three dictionaries are:
disfavor (v.)
To regard or treat with the reverse of favour or good will; to discountenance; to treat with disapprobation. (OED)
Regard or treat (someone or something) with disfavor. Lexico
To withhold or withdraw favor from m-w
Are there conditions or constraints (e.g. register) on using disfavor in the "neutral" sense of making something less probably or saying something is less likely, i.e. without denoting disapproval as in the above and following examples?
This fact disfavors the possibility that genetic personality differences are maintained by a mutation selection hypothesis. D. Buss et al.; The Evolution of Personality and Individual Differences (2011)
Such bias favors the finding of positive associations and disfavors the possibility that significant associations do not exist. But despite such inherent bias, the observed effects were small. H.R. 1633, the Farm Dust Regulation Prevention Act of 2011
There is, therefore a well defined line which limits the extent to which the general government can act as a moral person, and regulate its powers so as to favor or disfavor particular acts of individuals in the States. James Carter; Cases Adjudged in the Supreme Court (1891)
Is this meaning of disfavor so rare that it doesn't merit a dictionary definition?