Apple already makes this. It’s called the MacBook Air.
It doesn't have a touch screen. Which is what I thought we were talking about!
Apple came close to a notebook with a touch screen too ... but it seemed to be relying on Newton technology, as it had a stylus. It was a full scale (small sized) notebook though. Never retailed. I had a Newton and its (much criticised) converting written text to print worked fine for me. And my handwriting's terrible.
Apple's iPad profit centre are terrified that Apple might enable a touch screen on a Macbook. The reality is though that a Pad's benefits are related to its convenient size and if it doesn't have a keyboard attached, its weight.
I reckon the vast majority of iPad users treat the iPad as they did the early iPads and just use primarily for browsing. Add some use for communication. Some other tasks as well, which is where Apple has charged a lot more to enable slightly greater capabilities, and in the Pro capabilities that I reckon hardly any users utilise. No doubt the iPad cost centre see those capabilities as game changes, and vital. IMO they are marketing differentiators and are useless for the vast majority.
The facts are that with a touch notebook, they allow faster command approval because one doesn't have to find the curser and move it to a screen command icon that benefits the user if it can be pressed immediately. With touch, you finger does it instantly. Watching youtube and that advertisement comes up, then a skip icon appears - PC notebook users skip the Ad almost instantly without thinking about it. While MacBook users are still trying to find where the heck their curser is.
But if you go for a keyboard with an iPad, your iPad upgrade path is restricted. As is IOS for even M$ Office. But for students using cloud based apps, an iPad with a keyboard makes sense. But so would a iMac Air - but it lacks a touch screen. So many buy touch screen PCs.
And while the iPad is light - it isn't with a cover on it. And it's not as thin either with a cover on it. And with an expensive Pro, who wants to risk using it without a cover? And is thin better? I compared an iPad 10.5" Pro to the M4 Pro - my wife and I thought the 10.5" was thinner. Probably because it has curved edges. But it looked thinner to us.
This thread has had lots of talk about the weight of the M4 iPad. Which has puzzled me, because it's hardly any lighter than other iPads. Compared to the base iPad, the Air is 4% lighter, and the M4 Pro 8%. Add a cover and the difference in weight depends on the brand of the cover. And the cover narrows that percentage differential.
But the real change in weight with the M4 was in the 13" size. Today's 11" Air is just 16 grams heavier than the Pro. But the 13" Air is 103 grams heavier or 18% than today's 13" Pro. So now the 13" Pro with keyboard is as light as a !3" MacBook Air.