I actually think it's very good thing that people are asking that question (why not fix XMPP)!! We know from Bob Metcalfe's Law, that starting new networks has a very high cost, either in adoption/migration, lost investments in past standards, duplication of efforts when multiple need to be supported, or when they fail to gain critical mass. There's a limited pool of attention and resources and it's right for people to be instinctively cautious and have the discussions.
For me, the more I learn about Matrix, the more persuaded I am that it really does have merit. If I were a Matrix developer, I wouldn't feel disrespected. I'd be super glad that people are asking questions and genuinely seeking to test that the idea is right. From their dialogue with the community that I've seen so far, the developers are doing great and seem to thoroughly appreciate there's been a lot of false starts by various groups over the years.
TLDR;) - It may be obvious to you, but it's GOOD people are having the conversation. Questions and even dissent should be embraced. It's not about disrespect, it's about testing & validating new ideas.
I should add, that the ability to bridge networks, means that XMPP, IRC and others won't/don't need to be cut off from Matrix either. That's kind of the point and interop is one of the big features it will have going.
For me, the more I learn about Matrix, the more persuaded I am that it really does have merit. If I were a Matrix developer, I wouldn't feel disrespected. I'd be super glad that people are asking questions and genuinely seeking to test that the idea is right. From their dialogue with the community that I've seen so far, the developers are doing great and seem to thoroughly appreciate there's been a lot of false starts by various groups over the years.
TLDR;) - It may be obvious to you, but it's GOOD people are having the conversation. Questions and even dissent should be embraced. It's not about disrespect, it's about testing & validating new ideas.