I like the multitasking too, but my HOPE is that with the emergence of Apple Silicon that the iPad will basically turn into a touchscreen Mac. I get that the iPad was created for a different niche and all that (please, I'm not trying to incite any arguments there), but sometimes you just want a device that can do it all. With Apple Silicon, I TRULY believe that Apple can do it across the different platforms it has.
I say this not as a jaded iPad user, but I love my iPad Pro, more than any of my Apple devices. It's just that at the end of the day, I don't want to work around compromises anymore. I want desktop level apps on iPad and desktop level multitasking (and many of you have listed other wants/needs). Then I can eliminate some of the devices I have.
Of course, I'm sure that's not Cook's intent or desire, but all these teases that Apple releases with "What is a computer?" and Apple Silicon sure makes me think that they are more than capable of merging the lines and giving a desktop experience on the iPad (Pro).
I'm sure that we will see desktop-level apps on iPad, because universal apps are just that. While initially the big "party" will be getting all my iOS/iPadOS apps on my Apple Silicon Mac, that ship sails both ways. Mac apps developed for Apple Silicon can/will run on iPad.
As to Mac "multitasking" migrating to iPad? I seriously doubt it. This isn't about product differentiation, it's about user interface design based on the dimensions and constraints of the operating environment.
Technically speaking, we're not discussing multitasking (running multiple apps simultaneously), but the user interface that supports having more than one app/window open on-screen at the same time.
I can't begin to imagine the kind of undisciplined, open-windows-all-over-the-place, layer-upon-layer chaos I allow myself on a 27" Mac to work well on a 12.9" (or smaller) iPad display. Back when I had laptops (Windows and Mac), managing open windows/apps was a serious chore - I was always re-arranging - dragging windows around, resizing, etc. Slide-over and split view on iPad are definitely more disciplined/constrained than that, but I find that helpful rather than restricting.
Now that iPadOS supports switching between workspaces it's little different than using multiple Mac desktops - there's not much practical difference between Mac's Mission Control and App Exposé/App Switcher on iPad. Should the day come when iPad supports a second display, I'm sure the iPadOS interface will adapt in a useful way.
I don't use Mac's Full Screen mode on my 27" iMac (except accidentally). It's clearly designed to aid users of smaller screens - hide the Menu bar and Dock until they're needed to give the app's primary workspace as much room as possible. Don't you think this is very iOS-like? Basically, the smaller the display, the more useful it is to have a single app full screen.
I don't ever expect to see the Mac's Menu bar on iOS - a touchscreen device should not be menu-driven, even if the fraction of users who have physical keyboards might appreciate it. For them, perhaps the system could reveal those menus if the user so desires - but developers do have to put the extra work in to support it).
However, iPadOS has embraced Mac's Dock - it is graphical/touch-friendly, and a natural extension of traditional iOS. But I don't expect iPadOS to ever allow an always-present Dock due to available screen space.
Overall, I expect there will continue to be cross-pollination between the OSes, but so long as fundamentals such as display size and touchscreen separate them, I expect each OS to accept its natural boundaries. There are undoubtedly many iPad/iOS users who were never Mac users, so anything iPadOS adopts from Mac has to be done in a way that extends from the iPadOS/iOS UI language and traditions.