why would anyone just willynilly upgrade without running a test suite and allowing user feedback on it first? My users hate that we lost themes they loved (we're working on it), my staff hates that some of our addons ceased to function properly (we're working on it). These two issues ensured our main site is still 3.4.x (which is STILL supported) while we continue testing and resolving issues.
This gave me 1) happy users 2) happy staff 3) the ability to actively show the community what is going on in the test/dev ipb4 environment we have. You really can't blame anyone but yourself for unhappy users. Always test major releases first (this is a life lesson, not only applicable to IPB)
if you do run things in a test/dev environment provide feedback! perhaps some of the things you hate, love, or dont care about will be changed or modified based on your feedback. IPB4 is still getting updated fairly frequently (and for the better, IMO)