Even if you need to access the power button just once a year, it's annoying to have to lift up the Mac mini to do it. One advantage of having a computer as small as a Mac mini is that I can tuck it in to an unobtrusive corner of my desk. When I got the M2 mini, it was quite simple to tuck it in so that I could reach the power button if needed. But to find a position for the mini so that I can lift it when needed -- that's a lot harder. I need to keep enough space cLear around the mini so I can reach in and lift it. That's a lot more space than needed to reach in and press a button on the back.
If I were to get this mini, I suppose I could try putting it on the side or upside down, as other people have suggested. Hopefully, we don't have to actually lift it, just tilt it a bit to push the power button. But yeah, very curious design choice. Will have to check it out when this goes on display at the Apple Stores.