It’s not hard if you provide (at the very least) a comparably good experience. Ideally though the experience would be better. I know that’s not good news, but it’s true. People switch to a better experience. They’re already enjoying the social network experience. Harder to get someone that doesn’t even like social media to get into it.

Quite hard to provide a "comparable experience" against a 500 ppl engineering team operating on a limitless centralized server they fully control with just a few full timers and a bunch of part time folks while having to interoperate with 100 other pieces of software that were all written by different people.