People share negative sentiments for a number of reasons. Sometimes it’s emotionally motivated (like venting), sometimes it’s because you want to see less hype and more realistic discourse are about the deficiencies in our industry. There simply isn’t enough time to fix all the things that are problematic or completely broken, so naturally some things are only going to be talked about, rather than worked on.

And, I’ll point out the irony in your directive: you take issue with people expressing criticism without taking action to completely resolve the respective issue, and then you come along to express criticism by tell people to not complain but instead offer up free labor, when you could go and solve the problem that resulted in the original complaint.