Reddit will fizzle out very very slowly. A bunch content creators and mods that use 3rd party apps have left. What is left is the mass horde. It will survive on tiktoc and Twitter reposts for a long time. Like years... and eventually it will become stagnant and boring and the horde will find something new and disperse. It won't even be clear that this is what caused it or if it is the normal tide of the internet. To stay relevant you need to have progress that keeps people's attention. This move is a regression that will kill it in the long term.
I think you are correct. In later years it became more and more tiktok reposts and the same post over several subs. I saw a Ghostgum video when he compared it to the escape from Tumblr
Yeah, I think the big thing here isn't really users it's creators - I've tried various interesting things on Reddit, created some tools and bots because it used to be a great platform for that but going forward there's no way I'll waste time making them there when I could make them here.
A lot of the most interesting new things will get made here, especially with how flexible it is for people customizing their own instance to create totally new experiences. Over time there will be increasing more reasons to have a Lemmy account which will result in more people casually participating and shifting over this way.