That is the nature of bug reports. I was baffled by the reports that Android UI is "laggy" because I have never experienced this nor had anyone I know complained about it. That doesn't necessarily mean it is not happening to the reporter.
There are many many Android smartphones with many many different hardware stats. Even with low hardware stats to be cheap at the selling point. I can understand that this can lead to a lot of bug reports but if you have 5 devices and a handful of OS versions this is way better testable and fixable.
I could say "I can't reconstruct issues people have and until I see an Android device with laggy UI I won't believe it," but I won't.