I think it’s mostly that it comes across more like religious proselytizing than “good advice”.
Also, that “advice” is mixed in with just as much messaging about how fussy it can be and implications that you’ve got to basically be an enthusiast level user to make it work for you. Not that it necessarily is that way, but overall that’s the messaging I see from this community.
As someone who tried Linux many years ago, disliked it, and went back to Windows, generally my take is that Windows is far from perfect, but it’s the best option for me, and I’m happy to try and ignore the Lemmy buzz around it…but that buzz just gets more and more annoying over time.