PSA: You should know that Settings > Migrate Subreddits exists. All you do is login to your old Reddit account, copy a “multireddit” link, paste it in Voyager and you’ll be able to search the fediverse for those topics/communities to subscribe to.
You may find communities that are missing here if you’d like to run/manage your very own community on a topic you enjoy.
Hope this helps. I just found this feature today and subscribed to a bunch of communities.
I wish they hadn’t removed the option to use your Apollo backup. I installed Apollo and made a backup before Apollo shut down, and I still have that file, but I no longer have a Reddit account.