so modern laptops aren't great, they'll happily trade upgradeability and user experience for slimness every single time, but really if you're taking a laptop from place to place, you're still going to need to put it in a bag and then differences of hundreds of grams don't matter, particularly if it means you'll need dongles.
On the other hand, there are small form factor PCs like the tiny thinkcentres which do make the right compromises, have upgradeable RAM and take ordinary SATA disks, and have integrated wifi, with some even supporting low profile graphics cards. These things are tiny, my thinkcentre m83 is exactly 1L in volume in its case, and they will pretty much always use standard laptop power supplies.
You don't really need much imagination to see where I'm going with this, one of these tiny computers could fit within the footprint of a laptop and still be very tolerable and portable. You'd need to work out a case (you could prob shoehorn it into an existing one) a keyboard (... this'd probably have to be a very custom mech one), a screen (eDP), and a battery (idk tbqh)
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