Tbh, I think this whole thing is being blown out of proportion. Part of FOSS and the internet in general is the ability to have choice over what you use and spend your time with. Just because Sync is out, doesn’t mean you can’t continue to use your FOSS apps. It just means that we now have an option for people who want to pay for a very polished experience.
Just ignore them? I don’t see your point here at all. If you don’t want to eat Taco bell, don’t eat it???