> majority of enterprise software now (including and starting with Microsoft teams) outright say do not support firefox

Teams has explicitly supported Firefox for a while now https://learn.microsoft.com/en-us/microsoftteams/teams-clien... but the problem is "there's always another site that doesn't work right". Firefox usage share got too low, so places just check Chrom* and Safari work with the new feature and ship (sometimes not even the latter, if they don't care about mobile as much).

> there's always another site that doesn't work right

I keep hearing it, but personally I’ve only come across one recently (a site was running some tracking bullshit that broke on FF). And there’s one feature broken on LinkedIn.