Hello!
Currently I am a bit full on games right now, but I would be down to run another instance of Rime of the Frostmaiden (or a Wildemount campaign, but that requires more effort on my part and I am lazy u___u and I love RotF) with people in the future (in 8-12 months probably hahaha). Otherwise, as far as forum-based tabletop goes, there's a lot of sites that you could look into that fills that kind of niche. Aesthetically all of these sites are kind of... acceptable... they're not like, forum rp pretty. But that's okay!
rpol.net is a "bare bones" sort of PbP site but it has a few fun features, like being able to assign languages to individual characters so that when you type in a certain language, only the characters who have that language can read it. The
"Wanted - Players" board is constantly advertising new games in various systems, and 5e shows up fairly frequently. The atmosphere for games tends to be somewhat short posts, in my experience? A lot of the applications do not require a lot of effort, and the following play kind of shows that, I think. There's also little to no styling available for posts, and you have to use a pre-made icon for your character's account.
myth-weavers I am not very familiar with, but still fun! I see a lot of 5e games also advertised on this forum, and in my experience I believe this forum posts ads most frequently, so there's a higher chance of finding new games here?
rpgcrossing is what I would consider to be ... a higher effort, potentially-higher-quality forum for games? Of course there's always a range of "styles" and whatnot, but on this site in particular I see a lot of wordy, lengthy posts, and people who tend to put a lot of time into their characters. Applications usually are open for 2-4 weeks, and as a result the applications tend to be quite in depth — and it doesn't help that each person's applications are publicly posted to the thread, so peers are encouraged to kind of up their game a little. This site also has a higher staying rate, with many users having 1000+ posts on their accounts and being able to post very frequently. I am DMing Rime of the Frostmaiden on this site at the moment, and it's quite enjoyable.
rolegate is like... instant messenger x tabletop. I... personally... would not recommend it, but it's an option, so it's here. Just a small mention for it.
the pbp subreddit is constantly advertising games. Kind of difficult to get into them, as each game usually gets 80+ applications, and usually they are played on Discord and not very forum-y, and usually they expect very high activity (1-5 posts a day). But they're there! And it's sometimes worth it to pick and choose and see what you get. There's also advertisements for West Marches games, which are Discord servers that you make a character on and then grind experience with monthly quests and the like — not campaign, but like, a series of small one-shots, which can be fun!
Sorry I wasn't able to help personally! But if you don't manage to find luck here, hopefully you'll be able to find some luck on these other sites! I'm sure there's more sites and resources for you to check out, but these are just the ones that I have a passing or better familiarity with.
One day I'll get my DnD West Marches forum up too and then you'll have another option. Maybe. One day.Edit: haha, sorry! I see you're probably looking for IRL games. But my post was all about forum rp... Sorry about that!