For sure, and I agree with your post as well that things are starting to need an update now - again, that's more up to what is available to upgrade to as Intel has fallen behind on their yearly release cycles for the past few years.
Intel shifted away from their tick-tock model in 2016, to a tick-tock-tock. If You seriously think that Intel is loosing it's edge You read too many ******** blogs... I offer You this nice piece of insight... Marketing is easy, delivering is hard.
Apple's system as you has mentioned is great. Specific tools for specific jobs - and trying to make the best product in each of those categories they possibly can instead of doing the stupid **** that Microsoft and partners do where "once size fits all" and ends up not being great in any one single category of functionality.
It's two different philosophies (and then again, not so different after all), Microsoft tried the Phone OS route, but that was too little too late (thanks to Steve Balmer), since Microsoft more or less have dumped their Phone strategy, the only viable solution is to expand their core OS downwards, alas bringing their workstation OS to mobile devices and hopefully one day a phone - Apple also does exactly that, just the other way around. Apple is trying to position iOS as the go-to workflow OS, that's why you see iPad Pros, and it's why you will be more likely to see a 21" iPad before you see a MacOS surface you can touch.
But I really don't see Your point, bringing the same platform to multiple devices and sizes is the complete opposite of "one size fits all" - Windows can be made to do many different things, it seems (right now) mostly by blind UI designers, but that could (i hope) change. When you look into what's possible with connections to the Microsoft Cloud ecosystem it makes Apple look like Blackberry. "5Gb is sufficient storage" will be the new "640kb is enough for everyone"...
One thing I am really hoping Apple wakes up to and doesn't follow the path on... is dropping products like their Thunderbolt displays, for some plasticy piece of crap like the LG monitor. Yes, Apple monitors are LG and Samsung panels in a fancy case... but Apple (as you can see with the LG screen out now) takes that display, and marries it to a very functional and useful set of I/O ports that match up nicely with their systems and especially MacBooks, that turn the monitor into a nice docking station. On top of that, they make everything look visually appealing.
The I/O ports on the iMac is the same as what's on a laptop base-board, they left out HDMI, other than that, it's a laptop. Apple makes some of the best industrial design in the world, on that we agree. But they have given up on so much lately - how does it feel when browsing through that clean black/white world of Jony Ive that is the Apple Website only to end up with an ugly LG monitor with a black plastic ****-bezel. Apple is out of the stand-alone monitor game, get ready for an influx of ugly Korean monitors to flood the Apple store. But why stop there, how about a externally made Mac Pro, let's put it in this case or what about this?
Part of the reason I bought into Apple was that they cared about every aspect of a computer... from the case, to the cooling and cooling system noise, to the mainboard layout and internals being very neatly designed. Truly great systems for people who value true quality. A stark contrast to the cheap plasticy **** that are the typical off-the-shelf Windows PCs. The LG display is a big dissapointment and I hope they smarten up.
What cheap plasticy ****? You can get a beautifully machined aluminum Razer Blade Stealth, 512Gb SSD, i7, 16Gb, IGZO 4K Touch Display... an external Razer Core for hardcore gaming and/or impressing your very unimpressed girlfriend AND EVEN a GTX1070 for the price of a 13 inch Macbook Emoji. With 25$ to spare for a sticker that covers up that enormous eye-sore of a backlit company logo that Razer put's on their stuff.
You can always go get cheap plastic crap - but unless You are ignorant there's plenty of well-made and beautifully designed machines out there. Times are changing...