If you're on a 2 year cycle then upgrading this year seems like a real goer. A three year cycle means I would want to upgrade next year.
Of course we'll get better battery, the 6 times zoom lens and USBC next year, but the year after will be a significant change from the pill to the hole. I don't see the notch to the pill as anywhere near as big a change in that regards. Especially the smaller 13 P/PM notch.
Of course he could be wrong but we are about 4 iterations off having the full screen. If you time it right, that's only 1 upgrade between now and then. Again, if you upgrade every year, then it doesn't matter and you can enjoy whatever Apple puts out and not have to worry about what's coming the next year.