I think the main intention here is to block the bots. Reddit blocks requests coming from certain IPs associated with VPS and similar commercial providers. VPN services often rent exit servers there. My connection is blocked when it goes through Tailscale exit node hosted on a VPS.

You can use Tor to browse Reddit anonymously, there is even a .onion address

This is great, thanks for sharing! You’ve got a few useful feedback points, let me add one more: does a provider have an onion address. This allows decoupling of payment from usage. Not a big thing, but good to know.

I vaguely remember some issues with extensions in ungoogled chromium. Maybe I should give it another shot.

Depends on what you mean by “private”. I would not trust it much, but it’s not a bad Chromium based browser when you need one. Use something like LibreWolf for much more privacy out of the box.