Often times people on the internet think they are more techy or correct than they are. The other issue is this makes other users feel like the are actually less techy but the truth is an internet search can teach you a lot about how the Internet works.
My issue with the Lemmy community is that they think FOSS some how makes things more private and secure when that is indeed not at all how privacy or security works and there is enough evidence to suggest you are not secure no matter if it's FOSS or not FOSS.
There is also a mentality that paying for something makes it harmful or bad.
My argument for this is, "you will bother to pirate a game like Zelda for free because you love Zelda so much but then complain about Nintendo being bad because it walls things off. Zelda however would not exist without Nintendo and paying for Zelda would pay the devs to continue making Zelda even if it also means giving Nintendo money. So your logic is play a game you love but don't contribute to that game because you hate Nintendo?"
The same can be said about the sync drama. You want FOSS but can openly admit Sync looks nice and operates nice but you won't pay a price for something that seems better. Well the good thing is you don't have to. Sync isn't a problem because people want to pay money for an app that works. You are the problem however if you want to dictate how people use browse the web with an app of their choice.
FOSS is great. Lemmy wouldn't be here without FOSS but Lemmy's users decreased because Reddit's downfall and the community of users that came have talked about how poor some of the FOSS Lemmy apps are. However, they love Sync and sync also brought more people to Lemmy. People who are willing to pay. People who are making your platform more well known. An app like Sync is also offering a smooth experience and introduction to Lemmy and people will pay for things that work nicely.