Apple was the company that dropped the headphone jack from their phone, shipped a laptop with only USB-C ports etc... they don't shy away from making big controversial decisions if they feel like it's good for them.
If Apple was going to do this to MacOS, they'd have already done it. They wouldn't be spending years tip toeing towards it like people seem to think.
Instead, they've rolled back some really unpopular changes like the crappy keyboard in their laptop, they just shipped a new Mac Pro that is clearly designed for professionals. This chip transition will result in Apple's laptops having better battery life, specs and heating than any other laptops available on the market. It won't even be close.
Additionally, they're actively trying to bring a huge swath of developers who currently only develop for their mobile devices into developing for the Mac. If they were trying to turn Macs into something for college students to watch Netflix on they wouldn't be doing any of this.
It's insane to me that people can see a UI refresh as a sign of doom while ignoring that Apple has actually been investing in the platform quite a bit more than they were a few years ago.