It’s not so much the communities as the number of posts, I open Lemmy and see posts I saw yesterday only half way down the front page.

Communities for specific video games, like /r/wow or /r/ffxiv

The art subs, like r/art, graphic design, art nouveau, and all the AI art subs. I was mostly a lurker on those ones but they were really great eye candy.

Also things like earth porn and the nature subs. Was nice to see cool places in my feed.

And the local community subs. I think that will take a long time to develop (if it ever does). I used to get a lot of news on city events from Reddit and without Boost on my phone I’m feeling out of the loop

Trade communities like construction, electricians (my trade), and oshaviolations.

The subs for games like Street Fighter, the sub for fight sticks, the kind of semi-niche gaming communities that snowballed because of Reddit’s ubiquity

Most of the technology subs I followed have migrated to some degree, but I’ve noticed a lot of “normie” subs are still stuck. For me in particular, r/Writing prompts, r/nosleep, and r/YoutubeHaikus are sorely missed.

Right now I am missing the hyper specific cat subreddits like catswhoyell and catsinbusinessattire. There are so many that I loved to revisit every 2-3 months and see what was there

I miss the local subs for my city and other local communities around me. They were great for keeping up with what was going on. I can’t stand all the pissing and moaning on Nextdoor. There are a couple of Facebook groups but I refuse to install any Meta apps on my phone.

The subresdit /r/frugalmalefashion was really incredie for a while there, but it thrived in users posting good deals regularly and fair moderators keeping out inappropriate content (i.e. scams, predatory subscription services, and comments like “this isn’t truly frugal!”). /r/buildapcsales was the same way

I miss all my fun niche subs. Like mirror forsale, were it’s just funny pics of people who sell mirrors or take pics in front of mirrors.

Purple coco, sub for plugs in strange places.

Chairsinwater, its chairs in water and the flair was always NSFW.

There more but those are the top ones I miss.

stupiddovenests

AskHistorians

Best of Redditor Updates 😭

Prequelmemes, renfaire, antiwork, bikinibottomtwitter, raimimemes, insanepeoplefacebook, oldpeoplefacebook, Disneyvacation/notdisneyvacation, earthporn, novontextpics, marvelstudios.

r/whatisthissnake, r/subgenius, r/herpetology, r/bash (it is here! But it needs more users!), r/gpgpractice (not that I need it but it helps new gpg users), r/gameboy

Probably more but that’s all I can think of right now.