I dunno, I just don't see the big deal. Even if we ignore the fact Kid Flash does actually have powers Superman and Wonder Woman do not, like phasing through solid matter, why would he get worked up about it especially since he rarely interacts with them in any capacity anyway? His Super team is the Teen Titans, not the Justice League. It'd be like getting depressed because there are people out there you don't really know who can do your job but better and play the cello as well.