Typically Discord, but Discord has its own issues. When the Digg meltdown happened, Reddit was already a Digg clone at the time (this was the days before subreddits).

yes, we are waiting, the main thing would be their content and their communities. it's definitely not about the platform, but how it would be built and govern by the creator.

Lemmy, probably.

Most communities seem to be moving over to Discord, which is by no means a valid Reddit replacement (in my opinion at least) but it is the only option with decent popularity and moderation tools that are not completely unusable at scale. Lemmy is being thrown around as a "proper" Reddit alternative, but realistically it will probably meet the same fate as Mastodon: plenty of people will try it for a week or so, only to realize that the platform sucks and the content simply isn't there.

I've seen some move to tildes.

So far the best alternative that I've seen was Squabbles.io A lot of communities seem to be moving towards Discord. It has announcements, posts, chat, etc.

If Discord wins, we all lose. Even dead forums, online and searchable, are more valuable than live chatrooms.

It doesn't seem like it would be that difficult to clone the main elements of reddit. Hopefully someone is building one.

The user experience is easy to duplicate; getting good mods with good participants, blocking spam and bots, and scaling are the thing that will be hard to duplicate.

I wish Imzy was still around

TikTok is def eating into Reddit. People only have so much time to look at stuff and TikTok is taking a lot of it.