They work for me. Double tap is pretty reliable too (I use it for flashlight) - but be aware that it needs an unlocked phone (same on the Pixel 5). One trick that substantially increased triggering the utility: don't double tap with the tip of your f...
I find it pretty good, tbh. My other phone is a Pixel 5 and I've had many Pixels before. I think the sharpening it excessive on the Z9, but other than that the camera is quite good. It will never be Pixel-grade good, by which I mean primarily extreme...
I am one of those with close to zero issues. Had the same good experience with the Zenfone 8 - another phone plagued by problems if you just listened to the forums. I wholeheartedly recommend it, more so than the Zenfone 8 or, indeed, any other phone...