Hi, that’s fine. I was rather sure that pressing the home button dismissed the call w/o answering (one or two presses), so my response was pretty weak not very confident there, I admit. It seems intuitive enough to me and was something I have used since day 1 I’d think, since pressing the home button releases or dismisses most any app that one is in, so why not the phone app during an incoming call.
That's a fair point. I guess, personally I would assume the Home button takes me to the home screen. Wouldn't that be a more common intuition? If so, then that's also not great because the user wants to be back in their App obviously, and not the home screen. So then they need to think about what they were doing and how to relaunch it. In other words, it's creating unnecessary cognitive load for the user.
Also I'm kind of in tune with this feeling. Apple in their presentation yesterday at WWDC alluded to it multiple times calling it "taking the user out of context"
I actually wonder if it's maybe linked to a "doorway effect" in someway, ie forcing a context switch in the brain.
Scientists measure the "doorway effect," and it supports a novel model of human memory
www.scientificamerican.com
Forgetting why you entered a room is called the “Doorway Effect”, and it may reveal as much about the strengths of human memory, as it does the weaknesses.
www.bbc.com
First, as a huge proponent of keeping iOS intuitive instead of flat/unintuitive, I am all for adding the new method if it seems much more intuitive than pressing the home button for some or many.
Also don't forget new phones don't have a home button. But, you right, no reason they couldn't keep the home button thing as an additional function. It' is a tricky case, because if not a lot of people used it, was it a good UX feature? Or maybe it was a good feature but had poor discoverability. Who knows
I can’t stand when an iOS ”improvement” makes a commonly-used function less convenient by burying it off-screen. Hopefully this genteel notification is optional.
For sure, sometimes they "improve" things and oversimplify. Like removing affordances on UI elements in the new Big Sur which you mentioned in your first point.
I’m glad this less disruptive notification will be available for those who prefer it. I for one hope it’s adjustable in the notifications so I can keep the full-screen interruption to ensure I notice the call. I don’t mind being interrupted while instagramming my dinner or pouty duck lips showing my sadness over the iOS-ification of MacOS.
Pardon me to anyone who thought I dismissed your preferences as invalid.
Thank you for that. It's appreciated

And you right these things should be optional, so we can keep our devices personalized to the way we like them.
Bit of a detour:
Ya know, a few rather mean spirited and ignorant internet commentators loved to mock those that had an issues with zooming UI animations, or slow display refresh rates, or blue light etc etc. Of course, your comment was not this, it just reminded me of the times in the past where I would advocate for these features to be taken seriously.
Apple is now on board an have options to reduce animation for those with sensitivities, they're actively trying to bring 'pro motion' ie 120hz to phones without trade offs (e.g. by using variable frame rate), and have implemented true tone and night mode features. This makes me really happy and confident they're at the forefront of big tech companies thinking about how technology and humans interact (HCI) and how to make that smoother, calming and more delightful for everyone with a wide range of cognitive sensitivities.