Are you familiar with software development (not criticizing you here, but merely asking in earnest)?
First, you have to take into account the fact that Android doesn't belong to PA, but to Google. Therefore, there can (and will) be bugs that occur from the original source — that is to say, untouched Android.
Secondly, even if Android belonged to PA, it still remains a complex project, so it's hard to keep track of everything. That can sometimes translate into code regression. That is why, as a rule of thumb, you should only switch to a newer version if said version is a stable release.
On a side note, you should try your best not to insult the dev team — especially since, again, this is unstable software we're talking about. Attitudes like that can ruin the developers' morale, which can mean no beta builds available to everyone and/or slower release cycles. Be careful what you wish for...
If you feel the developers' answers are rude or cold, please keep in mind that they deal with dozens of users on a daily basis. They simply don't have a lot of time to allot to each user.