I'm interested. As a iOS developer I always found that user want to skip the login page soon as possibile, if there is an FB button they press it.
Do you have different experiences of it?
1) I don't want social media to track me everywhere
2) If the people developing this app have taken this shortcut, what other bad, leaky implementations do they have on their site/app?
-> No thanks, exit this way
We're actually getting rid of social login in our apps. And we're not alone, alot of platforms I use have recently moved the same direction, and I think for the same reasons.
Google, Facebook, Github, Twitter logins proliferated because
a) the cost of implementing an auth system is high, and those offered a turnkey solution that was cheap and quick to implement. This is no longer true, there are lots of options now to host your own auth while federating the hard work to someone else (e.g. Auth0, Cognito, et al)
b) for awhile, people LOVED the idea of having "an online identity" and a single login everywhere. Over time this has not really panned out, because it's the prisoner's dilemma; for it to work, everyone has to do it (which is why G and F have tried so hard to get everyone to use them). But also, because privacy questions have reduced the shiny appeal of that scenario in the first place. Combine that with easy to use password managers now, and it's much less necessary.