A simple Google search turns up results from years ago that are still valid today: https://old.reddit.com/r/discordapp/comments/ircyh1/locked_o...
> You'll be required to register a phone number to your Discord account in order to continue the use of it.
I didn't claim that it didn't happen to you, or that it never happens. You seemed to be implying that it will always happen, or commonly happen; my experience is proof that it doesn't always happen, and at least as strong evidence for it rarely happening as your experience is of it frequently happening.