No: an ad hominem is a specific thing, and this is not an example of one. For something to be an ad hominem, it has to make an assertion that—if true—would still be completely irrelevant to the truth-value of the syllogism, and yet will serve to convince the reader anyway, usually by the rhetorical power of the https://en.m.wikipedia.org/wiki/Halo_effect causing them to think that something that has irrelevant faults must also have (possibly unknown) relevant faults.

An example of an ad hominem: saying that someone must have cheated on their taxes, because they have some depraved sexual kink. Whether or not the assertion (“X is a fetishist”) is true, it is obviously irrelevant to ascertaining the truth of whether X cheats on their taxes.

An example of a not-ad-hominem: saying that someone is more likely to have cheated on their taxes, because they are an old rich white man. This might be stereotyping (i.e. inductive reasoning), it might be a “personal attack”, and it might be disallowed in a debate for any number of other reasons, but it’s not an ad hominem: being in the relevant class really does have some correlation (however small) with cheating on one’s taxes (mostly because all groups other than the relevant group consist of people with less access to the resources that would allow them to get away with cheating on their taxes.) Therefore, the truth-value of the assertion is not entirely irrelevant to the syllogism—so it’s not an ad hominem.