KPNW and KEXP are literally nothing alike, and I don't get why this trope persists.
KEXP is DJ selected, has many specialty shows, and what you hear varies with the DJ. A large percentage of the KEXP playlist is completely new music and often is very rhythmic or electronic. You sporadically hear more traditional "alternative" artists, but not in any regular pattern.
KPNW plays what are basically classic alternative and modern AC/AAA "hits" with a sprinkling of new music. In a way, it's the inverse of the traditional "play the hits" model - the station playing very few hits seems to have better ratings than the one that does.
I don't think most KEXP listeners have any use for commercials or commercial radio, and the "community" around the station is a part of the appeal. They're not reachable by commercial stations, because what could KPNW offer to convert people who are willing to pay for KEXP? A shorter playlist, commercials, and with the exception of Marco Collins, probably their air talent means very little to KEXP fans. Plus, apart from one song a day, to my knowledge he has no choice in what he plays.
I actually like KPNW but I can't figure out why their research didn't find a formula that worked better ratings wise. I also don't think KPNW is much like the station it supposedly is a replacement for (KMTT.) Nor do they seem promotionally active, I mean they do give tickets away through the app, but I don't gather that they actually send promotions people to any event, or do anything public facing that directly involves the station and engages its listeners. Maybe they should have let Collins program it, saved some of the money they gave Paragon, and hired a promotions staffer or two.