I never said SJ was consistent in those matters, but there was a time when it was iBook/iMac (consumer) and PowerBook/PowerMac (Pro).
As for your list, so? Today Apple offers 4 different desktops (not counting the Intel Minis as a separate line) and I don't think there was ever much overlap with 3 sizes of iMacs.
Apple could sell iMac in 4 sizes, a MacMini with MxPro AND a Studio with MxPro (aka no thermal throttling just as with the M1 MacBookPro and Air), a MacPro that goes down to M1Max but offers internal upgrades and so on.
But that is kinda what they did before Jobs came back.
The problem isn't so much with the number of products, rather than with their focus.
You can sell a lot of products while keeping them focused for their userbase, and you can sell 3 products without focus when only 1 could suffice.
An example? M2 13" MBP (and even the M1 before it). Utterly pointless, and still they have just released it.
Offering both the Studio and the Mini with the same chip would be pointless as well.
But selling an iMac in 2 size wouldn't be pointless, because there are so many people that are used to a 27" and want to upgrade without spending $3500 for a whole system. It's as simple as that.