Well, those parameters are intended for GA to parse, so there's several reasons for analytics competitors to not add those:
1) they make it easier for the marketer to setup campaigns with a paid competitor, and then drop the subscription for that software and monitor them with GA only
2) they make GA top-of-mind for marketers every time they look at a link with UTM in it, even in somebody else's marketing dashboard (free advertising for GA)
3) GA gets to collect campaign data, freeriding on the analytics competitor
1) they make it easier for the marketer to setup campaigns with a paid competitor, and then drop the subscription for that software and monitor them with GA only
2) they make GA top-of-mind for marketers every time they look at a link with UTM in it, even in somebody else's marketing dashboard (free advertising for GA)
3) GA gets to collect campaign data, freeriding on the analytics competitor