No, you are thinking about 70's computers. You already had the Apple II and IBM PC (the common ancestors of all modern desktop computers) at the start of the 80s. You also had the Atari, Commodore 64 or ZX Spectrum in the 80s. Computers are small and you have the prototypes for the form factors of modular hardware except for USB in place.
What 80's computing lacked was ergonomics. The controls are awkward and clunky despite not actually being that much bigger than their modern contemporaries.
The lack of cell phones can all be blamed on infrastructure, most planets don't have the population to support hundreds of radio towers for cell phones, but can easily pay the next dropship that comes by to loiter in orbit for a few extra hours in order to kick a satellite out the airlock. I just looked up a few modern satellite phones and they were both aroudn 250 grams.
Also the note-puter is probably bulked up by needing a dozen different ports to deal with the schizotech. Many planets are full of people having to choose between analogue displays that can be hand built locally or expensive digital displays they import from interstellar micro-fabricators. So adding RCA and Coax ports to any computer you are exporting makes perfect sense even if it adds unreasonable bulk by modern standards.
While the Commodore and Spectrum and the like were commercial PC's meant for the public, and the 80's was when mainstream computing was
beginning to kick off, most people's experiences with computers were still the clunky, room-sized mainframes and machines born from the late 60's and 70's.
It's just like how people's experiences with mobile phones in the late 90's/mid-00's were things like flip phones and small bar phones (man, I miss those), but all that changed when the fist iPhone and Androids were released a few years later (and then smartphones rapidly became the de facto phone 'format').
Until the IBM Clone craze later on, everyone went off and basically did their own thing with computer form factors, hardware, software, processors, et cetera. It was truly the Wild West of consumer PC design, and none of it was really interchangeable -- even software. You had to pay a guy to basically rewrite the program every time your massive computer the size of a room had a minor upgrade.
The OG consumer PC's, like the Spectrum and Commodore and the IBM/its Clones, basically started the change for all that, especially since they encouraged people to program shit at home with books.
Additionally, most people at the time still really didn't believe that home computing would take off the way it did in real-life, as it did in the late 80's and 90's -- they genuinely thought it would just be a passing fad or for enthusiasts, and most computers would be large and in the hands of businesses, banks, et cetera.
The IBM Clone Craze basically changed all that, as did the eventual emergence of the Internet.
And, ironically, it was Apple, Microsoft, and IBM who basically helped pave the way for what we have today (with their hardware standards, operating systems like DOS, OS/2, Windows 1, et cetera) in the late 80's and 90's.
FASA was, at the time, working off their presumptions of the future with the technology and culture they had
at the time, as above. We don't have such limitations because time marches on, although we'd be doing the same thing if we were trying to guess what technology would be like in the 2050's and such (again, to use the phone/smartphone example, no one in the early 00's would've thought there'd be a massive revolution in just a few years which helped change everything -- who knows what'll happen in the next ten, twenty years from here, right now?).
We can scrap that viewpoint they had and reinterpret Battletech technology through a modern eye (with scientific and technological advancements especially as a focus).
The Noteputer example you mentioned? Yeah, we wouldn't need about ten different data ports, unlike in the 80's when such a thing was common because the various computers out there were incompatible with each other at a fundamental level (remember, FASA at the time!). All we'd need is one or two USB ports. Need to access some of those clunky Inner-Sphere data drives? We'd create an extension which plugs into them and then plugs into a PC via a USB interface, as we do now with pretty much everything else "old".
All the clunky shit inside, like the retro-80's futuristic processors (which are probably still in the
megahurtz reaches) and form factors? No need -- a goddamn
Raspberry Pi or a micro-PC along those lines could probably do all of that and more, making its internals the size of a few credit cards... with a
gigahertz processor, even a lower-powered one.
Our version of a "Noteputer" would probably just be some sort of rugged Android tablet derivation, with USB peripherals.
That's how much technology has progressed, and how it'd affect reinvention/our interpretation of Battletech in-universe designs. And the stuff that in-universe Battletech does have which is better? We'd take it, learn it, improve it if we could through modern sciences, replicate it, and reimplement it. If we had help from a data core or remnants of Wolverine helping us, we'd do it even faster.
Also, the in-universe limitations you mentioned, like with the people just kicking up a satellite? We wouldn't be constrained by those limitations in-universe either, at least in our own backyard (Earth, colonized planets like Mars, et cetera).
Now, scale that up to
everything, from vehicles to Battlemechs.
And now let's dump this Modern Earth into Battletech, and watch the resulting fires. 👹
Frankly put, we're not limited by the design choices FASA made at the time
because of the times. We are, from FASA's perspective at the time, from the future.
(Also, I'm pretty sure that if a Ryzen Threadripper PC somehow made its way to one of the Inner-Sphere powers or Clans, they'd likely see it as either alien technology or some sort of supercomputer they'd try repurpose to manage central military intelligence, or something. shrug).
