Lemmy

There's an excellent style available through userstyles that might make the experience more bearable. If you have some technical skill and time, you could make one that looks and behaves as old.reddit. I expect something like that will appear soon there as I hear more and more complaints about the UI.

I'm pretty sure you can create your own bootstrap theme. If someone makes an old.reddit theme for Lemmy I'll add it to my instance.

PSA: you can choose your default theme in your profile settings. I'm pretty sure the themes available are determined by your home instance's options

If you can identify exactly which things you like about old.reddit, you'll have a much better chance of getting them as settings on Lemmy.

On paper there's lemmy-lite, but I don't know if any instance supports it.

There is also https://brutalinks.tech/

(Source-code: https://sr.ht/~mariusor/brutalinks/ )

It's not a Lemmy frontend, but an unrelated project similar to Kbin that also uses ActivityPub to federate. I am however not sure how well it federates with Lemmy right now. Probably needs some testing and bug-fixing.

Lemmy's UI in its current state is quite a bit of a mess. Hopefully this influx of users will result in devs that can help fix things.

I'd like to see more customization in general honestly e.g.: custom CSS (yes I know you can do it with browser extensions). I do agree that I think a more compact layout would be better though.

There is LemmyBB as an alternative frontend based on phpBB: https://github.com/LemmyNet/lemmyBB

An example instance run by the Lemmy developers: https://fedibb.ml/

It will only be temporary. I don’t get why they don’t close for new accounts for a few days though.