I use Last.fm which tags artists to similar ones, which is admittedly an older platform, but I also use Bandcamp, Spotify, and YouTube. It's trivial, I just search for bands that sound like whatever I like and sample their tracks. You don't even need music platforms to do this, Wikipedia has copious lists of musical groups for any given genre, or just the influences or affiliated acts of artists I already like. Beyond that, there's always been an ecosystem of music blogs and music journalism web sites since the early '00s, some still continuing today, and whenever they talk about bands they tend to refer to other ones.

You really just need a music platform to sample referenced acts, which YouTube is the universal one. It's really not that difficult.

Since this seems like a genuine question, nts.live is an online radio platform running out of London that has tons of good contemporary jazz. Try typing an old jazz song that you like into the search bar and find radio shows with that song featured. There will likely be new songs mixed in with the old.

In general, I find search engines to be a really poor discoverability resource for anything, not just music.

It certainly doesn't for me. Once you listen to things (presumably things you like), it updates your suggestions and offers a lot of more fine-tuned stations and mixes.