I can't tell if you're being serious. This basically reads like a parody of Tesla fans making excuses for Tesla.
If you're being serious, I'm not sure what you mean by "when we are all on MCU3". There is no MCU3, there's MCU2, and Tesla has said they're not upgrading MCU1 to MCU2. Probably you mean HW3, the new APE chipset? What about all the AP2 cars that aren't going to be upgraded to HW3? We just accept the bugs introduced by V9 for the rest of the time we own our cars?
Or maybe you mean that after they release HW3 they'll come back and fix the bugs in V9 for existing cars. That is a minimum of 6 months away, and if history is any predictor of the past, the first 12 months after HW3 release it will be buggy as heck and they will be spending all their time putting out fires (major bugs that brick cars) and struggling to reach parity with HW2/2.5 on stability and performance. So what you're saying then would seem to be that we should shut up and live with the V9 regressions for 18 months.