I mostly agree, I would like to have gotten split view multitasking on an external monitor for older iPads but everything except the M1 still just mirrors the internal display.The real thing that has been holding back the iPad has not been an inability to have overlapping resizable windows, but rather the fact that most iPad apps have not had the full feature set and functionality of their desktop counterparts.
Many of you are ignoring the fact that based on what we saw during the keynote, iPadOS 16 is addressing many of the actual functional differences between stock apps on the iPad and on the Mac that have been holding the iPad back – and I don't recall any of those being limited to newer iPads.
Apple has known for some time that it can't source enough components from suppliers to meet current demand for the iPad. It's a supply issue, not a demand issue, that is holding back iPad sales, so there is no reason for Apple to artificially limit features on older iPads to drive sales as some in this thread are suggesting.
We are also not getting but in format pane support (the iWork sweet on the Mac has that nice right hand format pane which is persistent rather than the popovers that the iPad version has). I would like to have seen more extensive virtual memory support across older iPads as well to allow apps to continue performing long running tasks in the background.
For the last few years it has been a case of developers not bringing the full feature set to iPad and I think that will continue - I suspect part of the problem is the monetization model on iPad not being as good as on Mac.
Generally the iPad is pretty close to where I want it already - multi-windowing with resizable windows is, I think, of very very limited utility compared to the rest of what they announced but we will have to wait and see if the apps are updated to take advantage of it.