Proper english grammar and left leaning political grammar are very different examples. If Microsoft introduced religious grammar suggestions it might offend a few people and provide benefits to others.
That there is such a thing as “proper english grammar” is itself inherently contentious and political. DFW's review of Authority and American Usage unpacks this a bit, if I recall. It's hard to find online because it's still under copyright, but I found this: https://web.ics.purdue.edu/~drkelly/DFWAuthorityAndAmericanU...
I don't agree that it's political but I do agree that it's contentious for English. However, if we see this as a template for other languages, it makes more sense what with Spanish, French, etc having rigid definitions and control[0] over their respective languages.
With all due respect to descriptivists, when engaging in any sort of formal communication (written or spoken), prescriptive grammar matters. There are "proper" and "improper" ways of communicating on a formal level.
"Ain't" is a perfectly normal construction in some dialects of English, but if you use it in a formal setting, people will notice and will think it's strange.
It could be useful for a product like Google Docs to tell you not to use dialectal grammar like "ain't." If you're writing a formal document, you probably want to avoid that kind of language. However, if Google Docs goes beyond that and starts telling you to replace completely normal words like "blacklist" with woke alternatives like "blocklist," that feels more like an attempt to establish some sort of religious orthodoxy. It gives the same vibes as if Google Docs were to start trying to push Evangelical religious sensibilities on its users. It's not helpful, unless you think your audience is extremely uptight and you want to avoid upsetting them.
Descriptivist language can absolutely describe things like "ain't", by saying "here's what it means, and also here's how you'll be perceived if you say it". Similarly, descriptivist language can tell you what people mean when they say "irregardless", and also tell you that it's commonly perceived as incorrect usage. (That's more useful than just saying "that's not a word".) You can look up a slur in the dictionary, and you'll find it there, along with some history and context and how the word comes across to people. Descriptivist language includes "how formal is this", "how offensive is this", "how correct is this", and so on.
It's useful, especially for people who aren't already steeped in cultural norms, to have a reference for "how might I come across if I say this". Words simultaneously communicate meaning and connotation, and it's helpful to understand both the meaning and the connotation. People aren't going to misunderstand the author of a text that says "blacklist"; they're going to understand just fine, perhaps including ways that the author would prefer not to have been perceived, or perhaps in ways the author intends to be perceived.
Tooling like this won't change the minds of people who are determined to be offensive (with or without the added assertions that they don't think it should be considered offensive). The point is to inform people how they may come across. It would be incorrect to say "this word is universally considered offensive", just as it would be incorrect to not label the word at all; it'd be more correct to say "this word's status is [disputed/transitional], with [an increased trend towards being considered non-inclusive], and consequent [doubling down by conservative language users]; consider avoiding due to any or all of offense, controversy, or politics".
"Ain't" is pretty universally viewed as informal language, and therefore out of place in formal communication.
Until just two years ago, "whitelist/blacklist" was completely normal language with no racial connotations, and I would wager that it's still viewed as completely normal by the vast majority of people. However, in just the last two years, people of a certain political persuasion in the US have decided to make these phrases into an issue.
If it is critical for you to communicate and come off well to a relatively small subsection of upper-middle-class liberal Americans, then these suggestions might be helpful. If it is critical for you to communicate with fundamentalist Evangelical christians, then a different set of suggestions might be helpful. I view the two situations in exactly the same way. However, if you're just writing for a generic audience, then these suggestions come across as unwelcome proselytizing.
