I’ve tried everything too, but everyone wants to play indie covers or punk, which I can’t stand. I’m trying to establish some links at the university where I work, as there’s a number of musicians on staff who might be up for a jam. Perhaps that’s worth a try at the university or college near you. Many have quite generous outreach programmes offering free lessons and so on and may have some useful info.
Be prepared for a lot of time wasters though. I put this advert up and a day later had TWO people write to me saying ‘Do yOu wANT to PlaY PunK CovErs?’
https://bandonkers.co.uk/fusion-funk-bass-player-available-york-14177