I think it’s fair to ask why Apple thinks iPad OS is powerful enough as is. Unless they’re intentionally holding it back so certain power users buy both an iPad and a Mac. But I don’t think that’s defensible.
My answer is that the iPad is designed around select use cases in mind, which may or may not jive with your definition of what a power user needs.
And if you ask me, I have identified 3 primary areas that the iPad excels in over a Macbook.
1) Viewing content - made better with the tandem OLED display. According to Christopher Lawley, a YouTuber, the M4 chip allows him to view photos in Lightroom without breaking a sweat, something that even past iPad pros would struggle with from time to time.
2) Digital canvas - made all the more so with the addition of the Apple Pencil. Procreate is like the poster app for the iPad, and it has been invaluable to me as a teacher.
3) Computing made simplified. It may sound like a contradiction given the existence of the iPad Pro, but I maintain that the beauty of the iPad is precisely that it does not try to mimic the Mac at all. Think about all the things you do on your phone because it's more convenient than on a PC. Now, you get to do them on a larger screen. It's thinner, lighter, more portable, and easier to carry around and use in positions and locations where a laptop form factor may not be feasible.
And it's precisely because Apple already has the Mac that the iPad is free to be as light as it is and does not need to try too hard to cover all conceivable use cases under the sun the same way a PC does.
I can understand people desiring more functionality that makes them not need to have to keep reaching for their computer, but their absence does not make the iPad any less than what it currently is, and honestly, how often do you need for format a drive or interact with terminal (I personally have never launched the app).