Has the accuracy of the snapshots actually changed based on this edit? After all, if it’s factual information being presented…

Yes! Quite literally, yes. They’re supposed to be an archive of what is on other sites. It doesn’t matter if the original site was, right, wrong, complete, incomplete, accurate, inaccurate, factual, unfactual, etc. If they change things, they’re editorializing and are no longer an archive, they’re new content - which is not the purpose people use them for.

I do agree that it raises the issue of what other modifications there may be,

That’s literally the point. It doesn’t matter how much you “understand the reasoning” (though you also think it’s childish and don’t agree with the actions). You can use it if you want to, no one is stopping you. The point is Wikipedia can’t trust it as a source of archived data and has every right to ban it.

That’s inappropriate, childish, and unprofessional. It makes them untrustworthy for citations. There are better ways of handling it.

If altering snapshots for a grudge isn’t your definition of “behaving poorly” for a site archiving the state of the Internet, then you must not think they have to be an accurate source of information. If they’re not an accurate source of information, then Wikipedia has no obligation to allow them to be used in citations, and they should remove such citations.

It sounds like archive.today is behaving poorly. As far as I know, Wikipedia isn’t exactly “big money”. If you know different on either front, can you please explain. Otherwise your comments are meaningless.