Obviously #Fediverse is more than just Mastodon. I am not sure if #Pleroma and #Misskey offer RSS feeds of accounts and hashtags — would love input here!

I know some other fedi instance software also does offer RSS feeds. For example, @Castopod does: https://podcast.tomasino.org/@SolarpunkPrompts/feed.xml

Anyone who knows about RSS support in other fedi instance software, please do jump in and share!