How a request is delivered should not determine of the request is valid or not.

I agree.

Most adults realize that diplomatic requests get fulfilled more often or with less friction, but the onus should be on the developers to be thick-skinned enough to parse through mean words and identify valid concerns.

Again, I agree. I agree with MrPotatoWarrior when he said that it is insulting to the developers to assume that they would stoop that low and to not communicate on account of the toxicity that can be found in gaming forums such as this one.

Just because "it's their job" to waive through it doesn't mean that it makes anything any better, though. What is the practical benefit of having this rubbish feedback that, often, doesn't provide any usable information for Team 5?

Making demands, especially demands not supported by logic and reason but rather by greed or ignorance, is not a good way to go.

other people clearly disagree.

In that case, I'm open to a discussion on what is and isn't worth demanding, because thus far I've seen nothing that is truly worth demanding. Changes to Warsong? The key problem with her was neutralised, and Warriors in Arena have been boosted further. It would benefit Warriors, yes, but is it really such a game-breaking or anti-consumer aspect? Definitely not.

Come to think of it, the closest thing I can think of right now that is worth demanding is a change to Arena rewards. It directly influences the return-on-investment you get, no matter how many wins you end up with. Even so, I think just delivering that feedback in other ways is just as reasonable. Find a way to open discussion, rather than putting something on their plate and telling them to eat it.