Yes, the hashtag feature works for me. Are you logged in to Pixelfed? It seems like you have to be logged in to be able to see the hashtag feed.

Yes, I have a user on pixelfed.social. I like it, and use it daily.
It is kind of like Instagram, but in the fediverse and is open source.
A cool feature Pixelfed has is the ability to follow hashtags, so your home feed will be a mix between posts from the users you follow and the hashtags you follow.

old.reddit.com (and the .onion one) works in the Tor Browser, for me at least. I am not logged in

There are some BSD communities on Lemmy/kbin, but they don’t have many subscribers yet.
Here are the ones I know of:
@openbsd
@openbsd
@bsd
@netbsd
@bsd
@freebsd
@freebsd
@netbsd
@bsd
@freebsd
@FreeBSD

I have Jellyfin installed on my homeserver, works great for listening to music in my opinion. I sometimes use Bandcamp to find and buy/download music, which I then upload to Jellyfin.

I created a GitHub repo a couple of weeks ago to list merch for open source projects, but there are not many things there yet.
https://github.com/makmarian/open-source-merch-list

Note: I’ve tried to make sure I found the correct link for each project, but if unsure, please double check. Also, I have not bought from any of the links listed, so I cannot say anything about the quality of the different merch.

I’ve been using EndeavourOS with KDE for a bit under 2 years now (I think) on both my desktop and laptop. It is Arch based and easy to install. And for my home servers I run Proxmox