This conversation is probably irrelevant, people have been asking for a veto or a return to the Zep pool for years and apparently the dev time and interest for working on it don't exist. But I really don't understand how you figure the top of the ladder, where the pros and tryhards are, should be designed to support participation while the rest of ladder, where the casuals are, should be about forcing people to push themself and having less fun for the purpose of getting better at a niche game in a niche gaming genre. Matchmaker should be just that - a way to get a match - and if vetoes help* and are technically possible then they should be applied for everyone.
*While I would personally like vetoes, it's not a deal maker/breaker for my ladder participation and I'm not sure it would actually help much, especially at high levels where people have mastered game mechanics and are looking for a fresh challenge through map variety. So I can understand why devs don't wanna spend a lot of time on it, would be happy to be proven wrong though.