You're full of shit.
You said OP support was helpful and did their best? You've had multiple repairs but remain sceptical that they actually did anything? Doing a factory reset and putting the same crap on it won't really help you much. Hardware easy to check and diagnose but config/carrier issues are far harder and I'm guessing that's where your trouble lies.
Getting a free 7T to appease you for not being happy with their repairs was a greet bit of support. Just because they did that doesn't entitle you to a replacement phone each year if you find what you think is a critical issue? Ffs you'd have people driving 2022 cars despite only ever buying a 2002 new.... Critical fault must gimme new car..... Critical fault must have new car etc..
You expect us to believe you're so unlucky you've had 7/8 critical hardware failures from OP? 6T with multiple repairs with main board which is like a new device and then the 7T etc...
What the fuck do you want my guy? They even offered you a very cheap 8T 4 years after you made a purchase but you think it's no good? The truth is you thought you deserved a 9 Pro at that price which is entirely unrealistic.
Consumers like you fuck it for the rest of us. No idea what you're doing and no chance it can be anything on your side just critical multiple maximum hardware failures that can only be resolved by giving upgraded devices free of charge.
Get to fuck.