There is practically no difference in these requirements versus what Facebook is requiring. Try to create a Facebook account and they will soon flag your account to require a photo for facial recognition. You can't signup for Facebook without a valid mobile number. And if Facebook does not like the photo you provide for facial recognition, they want a government ID.
Mmh no? I've been without FB account for 3-4 years, and recently opened a new one from scratch because some friends only use FB and absolutely nothing besides confirming my email was required.
Yes, it does suggest that I add my phone, and that I verify my friends, and that blablabla, but nothing else is required for me to add few friends and join a chat.
I'd been without a Facebook account for four years as well, but created one for testing/verifying the behavior of an application we'd recently gotten approved.
As far as I'm aware it would not let me create an account without a mobile number to confirm the account.
After performing a single action (creating a page), my account was flagged, and thrown into the facial recognition captcha process.
See here for many more anecdotes about this process:
My bet is that they were able to internally link your previous account and the new one. And probably kept building your profile while you were "without" an account.
