Although that is an intriguing (and controversial) possibility, Apple has never explicitly stated that. What they have done, is continued to heavily invest in the Mac lineup. IMO the βProβ in iPad Pro is meant to target creative professionals, not all the types of professionals (for e.g. programmers).
The iPad division was advertising their product with taglines like "what's a computer" and phrases like "desktop-class" that indicated Apple - or at least, the iPad division at Apple - considered the iPad to be a MacBook replacement, not just a companion. And they still do this, even now when the Mac team is actually putting out good hardware again (ironically, by putting iPad chips in them).
You second paragraph - you need to understand the audience. For most average people, they don't need a Mac. They need a web browser, a banking app and a few other sundry apps for casual tasks. For the pro artist, they want a canvas. The iPad fits that fine. With a keyboard it is a very capable computer, with a pen it is a very capable canvas. Even for professional workers, the iPad can be enough if all they are doing is creating documents[1]
The MacBook Pro/Air is for anyone who - want to code in general and/or wants to create apps for iOS and macOS, wants to use addition hardware that requires extra power to be used (music production interfaces for example, or other types of compute module), needs to multitask, needs to consume files from different sources (local, usb, network etc)... etc. So, professional people, or "power users". This includes those that simply prefer a traditional computer. This is a fuzzy cross over. It is not precise.
The M series chips are not "ipad" chips. They are just chips. They happen to be used in multiple places, but this is no different to using an Intel chip in a tablet (which for sure happened. I owned a Windows 8 tablet that had the form factor of a Nexus 7 tablet.)
[1] Anecdote - a guy came to my house last week to do a survey for some heating system changes, and all he had was 2 ipads, a printer and his regular tools. All the documentation and quotes he printed on-site, they all came from the iPad Pro he had with a keyboard. The other one was most used to survey, he had a thermal camera to look for where out underfloor heating was laid as we don;t have the original owners installation documents.
To be clear, as an iPad Pro owner, I don't think "just put macOS on iPad" is the answer to the iPad's problems, either. But I can appreciate why people complain about it. Apple sold them "a computer", they want "a computer". With full iPad ports of Mac apps, a filesystem that isn't entirely built around share sheets and hope, project exports that don't demand you keep the app foregrounded because Apple can't be arsed to add a "Eat The Whole Battery" multitasking mode, multiple user profiles, third-party developer tools, third-party app distribution, and generally, the ability to innovate on the platform without Apple's prior written consent[0].
The iPad was originally announced as Apple's answer to the netbook: a cheap(ish) touch computer for casual computing tasks and games. In that narrow lane, it succeeded. But in 2015 with the introduction of the iPad Pro, Apple decided that the iPad was going to replace the Macintosh. The Mac was there to be to the iPad what the Apple Lisa was to early Macs: an annoying technical relic to bootstrap software onto the newer, superior platform. Except Apple didn't have the courage to pull the trigger on several features necessary for creative and development workflows on iPadOS until it was too late. e.g. The reason why iPadOS is built so heavily around share sheets is because, for the first six years of the iPad's life, that was the only way to share data between apps[1]. So there's a lot of old apps that do things the annoying way, a lot of roadblocks that get put up arbitrarily, and so on.
[0] More broadly, the creative economy needs to stop talking about consent. Consent is for sex, not creativity.
[1] iOS 9 (?) added support for shared containers, but AFAIK each app that wants to use the container has to opt into it; and all apps have to be published by the same corporate entity or otherwise consent to data sharing in this way. There was no way to just have files owned by the user and nonconsensually modified by other apps.