It really depends, support is usually the first thing companies adjust when they want to improve their margins.
Even when you're paying millions to AWS you have to get through their first line of support and they will ask silly questions until you can convince them to escalate.
Not really, you get "really dedicated support" at most, but not a "really good" one, otherwise all those decades-old bugs common in many software producs would've been fixed since they affect people at all tiers