Given the unprecedented attacks on trans folks and the much higher murder rates of poc queers I think giving them space on the progress flag is more about making a statement about inclusivity and intersectionality than anything else.
Trying to include more groups like bisexual is just missing the point and people arguing that the progress flag should stay the way it is (although no one is talking about the intersex inclusive one which is an interesting statement on the erasure of intersex individuals), is more about the recognition of that statement and trying not to water down the message with a dash of design because it’s already pretty crowded.
Ultimately I do not care which flag you fly. It’s okay to say that you don’t like the design of a particular flag, but you should stop a second before commenting that and think a bit about what you could possibly accomplish with such a statement. It’s not your flag and you’re not flying it, so ultimately does it matter what you think of it’s design? Do you walk up to people with shirts you think are designed poorly and say “your shirt sucks, get a new shirt”? All you’re going to do is make them defensive and you’re pretty likely to start a fight, especially if you go off on some weird tangent about how you think the flag is bigoted in some fashion. The old adage ‘if you don’t have something nice to say, don’t say anything at all’ is pretty much designed for situations like this.