I used to go to Folklife every year but I haven't been for a few years because I got tired of running into folks I didn't like because everyone in Seattle goes.
Also in recent years the police presence at Folklife has gotten crazy. SPD sends out hundreds of cops to patrol the area on bike and foot looking to bust folks for smoking weed or drinking in public. Ironically enough, they didn't give a shit about people smoking weed there back when recreational use was illegal. ¯\_(ツ)_/¯
That said, it can still be a cool event to go to for the music and to meet folks. There are always tons of traveling kids and you'll have no trouble finding other musicians to jam with. If you find a good group to busk with you could definitely make a good amount of money. One year my friends and I brought kazoos to Folklife and tried to busk with them as a joke and people actually gave us money.
Anyway, I'll probably bus down to Seattle for it this year to check it out and would be down to meet up with any StP folks who may find themselves there. Maybe I'll try to get another jaw harp to join the musical fun.