You are indeed blessed in not having experienced any problems yourself. If only we were all so fortunate.
Unless I (and others) completely misunderstood your reply to Aalexsa, the comment “it was widespread, we'd have heard about it by now” perhaps suggested that problems don’t exist.
Speaking for myself only, since release of the production version of iPadOS 15.0/15.1, I have personally experienced and reported every one of the issues that that I have listed above - plus others - across both iPad 12.9” M1 and iPhone 13P. I have also spent considerable time addressing these and other issues, reported by other contributors within these fora. As such, I believe it is entirely fair to say that there are genuine problems being reported here and elsewhere.
I remain hopeful that the many issues are addressed in short order, as iOS/iPadOS15 has great promise in its advertised (but as yet unfulfilled) feature set.