I don't think Latinx is a good example. The GP mentions there's no functional cost to `main`, and this is true. Latinx has a functional cost in that the Spanish language literally does not support the phonetics of Latinx.
That phrase is going to die soon and it never picked up in Latin America. Most likely the queer community in Latin America will come up with more effective slang. It took the US queer community decades, a century? To reclaim and come up with effective phrases -- I think the main issue here is lack of patience and a somewhat condescending attitude from American liberals that we, the actual hispanic diaspora, need our hands held.
There is also what I've argued is a hierarchy of needs issue at play with LatinX. The problems facing the queer community in Latin America are more severe than those facing the US community, because it is a younger community in a more conservative atmosphere. Therefore, the effort is better spent advocating for table stakes, like marriage equality in some countries and reduced violence towards queer people -- there is no time to be wasted, right now, on the exact, precise terminology to use. And LatinX is not a way to win hearts and minds in this process.
Edit: this is NOT support for Google's product, which clearly broken and not useful. This is an explanation of why LatinX specifically is not a good counter-example to `main` versus `master`. I hope this pre-empts someone coming in and calling me all 'woke' or whatever is the cool phrase for dismissing people these days.