You want people to be able to have a low quality video of them noodling or playing along to something for 30 seconds.
You’re acting like young people wanting to join a band don’t know how to post things on the Internet.
My comments are literally based on the disappointments in using similar sites in the past. Most people don't add audio. Profiles without audio are useless. Making (and possibly providing minimal vetting?) people post audio would already be a big step in the right direction.
And again, most drummers and bass players don't create complete tracks on their own, and they're the main thing people are looking for. And honestly, a lot of drummers and bass players don't want to come into a band where the guitar player has already decided what the bass and drum parts should be. You can get a lot from listening to sketches / noodling. (By noodling I mean mainly improvising something unaccompanied, not necessarily trying to win the gold medal at guitar gymnastics.)
I'm a bass player. A younger version of myself lived from playing bass for a couple years. I still play quite a few gigs. I very, very rarely produce tracks (one every few years), and there's very little of my bass playing online.
As a bass player, I want to hear if the singer can sing, and if the sketches of songs are good.
I can also play all of the standard band instruments at varying levels of competence, but I'm not much of a songwriter. What people expect from bass players and drummers is that they are good at catching things quickly and writing interesting parts.