Reading this on my Fairphone 5 and can't reproduce this issue. But I admit that sometimes I just want to see the lock screen and accidentally unlock the phone. Therefore, I still agree. The back is the better position for the fingerprint reader.
It rarely happens right when locking the phone, mosty because I already developed the habit to press the power button not with the tip of my thumb but lower down, where the joint is. But when shoving it back in my pocket it still happens on a regular basis, even when I try to avoid it. The button is just located in such a way that it's very hard to avoid touching it while doing so. Then I pull it out a while later to find I changed 20 settings and made a dozen in-app purchases. ;)
Not sure if there was an option, but I would not want to enable it anyway. I want to avoid baby fingers to enable the screen ;) I remember I enabled it with my previous phone, though, so could work for some.
that also never happened on any of the string of cheap chinese phones I installed lineageos on before deciding the world was sketchy enough to mean grapheneos was the minimum viable level of hardening for my phone. I miss the power button fingerprint scanner dearly.
I'm sure it's manageable with proper software, as I had no such issue back in the day with my Xperia Z5(?) compact.
(That said, I get similarly cranky about various gestures that just don't reliably work in some cases. I despair of the eventual day they (google in my case) no longer offer the 3 button home row on android phones)
With many phones these days you can suspend by just double-tapping the screen, or the status bar. Sometimes this works for resume too, other phones require a physical button press.
Who came up with that idea?