Except they aren't. Apple continues to keep macOS and iOS/iPadOS as separate operating systems and features.
The iPad Pro doesn't come with keyboards, trackpads, or styluses by default—it's designed as a touch-first system, and MacOS remains without touch capabilities. That they are trying to unify software capabilities is less about iPads and Macs merging* and more about reducing developer friction to support all their platforms.
Apple wants to sell more iPads, which they see as the future of computing for a large audience. In order to do that, they have to make the machines viable replacements for laptops. Hence, the moves they've made. That's completely different from the thought process that brought Microsoft to its convertibles.
*On an infinite timescale, are Macs and iPads going to merge? They might. But I'm not sure how that would make Apple "copying Microsoft" if ten years down the line they arrive at a similar point via an entirely different method. I also wouldn't hold anything Apple says as an ethos in high regard; Jobs was famous for publicly and loudly ******** on Feature X as something no one would need, until Apple had created Product Y that had Feature X in it six months or a year later. If anything, Apple under Tim Cook is more consistent than Jobs, not less.
