The question is whether Tesla is deteriorating as they scale. Those that bought their first Tesla recently during/after the scale up, which are many M3 or MY buyers should be bias favorable to Tesla. Many of those buyers have owned their cars for 2 years or less- if they’re relevant to the service question it confirms Tesla is one of the worst. Hell, even my JLR product didn’t need much in service in the first two years.Long before Tesla existed, most people rated the car-buying experience somewhere between root canal and colonoscopy. Lemon-laws have been on the books for decades. So I think it's fair to compare Tesla to other manufacturers, rather than some arbitrary scale of perfection.
That said, an online message board makes for a poor random sample. There are numerous studies of Tesla ongoing service and quality issues:
Tesla quality - Google Search