Right... Funny how you seem to forget how crappy early X.0 Android versions were. Go and look for it.
Almost all early Android versions are riddled with issues. The reason you hear less about it is that it often takes a long long while, even months, before a substantial number of people have it. Adoption curves show this quite clearly.
In one day, IOS can be on more phone than a new Android version will be in 2 months.
That kind of exposure reveals obviously a lot more edge cases, especially on earlier devices.
Often new Android versions are on new phones initially certainly not 2 year old phones.
So, what on earth are you even comparing!
I could go look for it, or I can look at how much faster and better the Pixel XL ran after the Oreo update. I don't know where you're getting your information from.