not grandparent, but this topic is oft-discussed (but with no clear resolution!) on r/realtimestrategy
imo, the biggest obstacle is the combination of
a) RTS not being well-understood
b) sweaty streamers broadcasting the idea that the games are "solved"...but only enough to criticize you for not being "optimal," not enough to actually help you approach the game.
These add up to a very intimidating picture, unwelcoming for newcomers.