I stopped using streaming services as I tend not to listen to music in the way they want. I always listen to full albums in order and tend to listen to albums on repeat. I tend to focus on my music, and want zero interruptions, so an offline, dedicated music player works best for me. I can't stand my music randomly disappearing, so I purchase it all. That means I am reliant on finding new recommendations based on something other than my listening history!
I primarily subscribe to the RSS feeds of a few smaller review sites and blogs. I listen to a specific subgenre of metal, and so angrymetalguy.com is one of my favorites.
I also heavily use bandcamp. Because I listen to a more niche subgenre, the labels tend to be small, independent labels that only focus on that genre. So I subscribe directly to the labels in bandcamp, as they advertise new artists and releases on their label.
Bandcamp only supports using their in browser feed or getting emails, which I find annoying. So I use imapfilter to automatically convert those bandcamp emails into an RSS feed.
I also follow a few subreddits that just post new music for very niche genres to help find some things I might have missed. I also pull these in via RSS.