"dealer" was the problem there.
I am sure there is some radiator of sufficient size/cooling that would fit. More than likely it would have required some creativity, creating special mounts, doing something possibly odd like stacking two of them, using something from a different OEM. Which would have gone down a little rabbit hole of needing different hoses or using ones that are not molded, fittings to adapt sizes etc.
No way it was really an unsolvable problem. Some shade tree could have done it but dealers don't like things coming back that isnt their model. Anyone who has ever built a custom or maintained a legacy vehicle with limited support knows sometimes you have revisit 'solutions' after you drive a round for a week to get things 'dialed in'
The firmware stuff is/will be different. Right now the modders and tinkers enjoy some advantage in they have known working examples to look at. When you sitting in your garage Sunday afternoon trying to get your 40 year old car to work, first you'll have find stuff that is electrically and mechanically compatible, then after that you'll have to deal with the software (often deliberately designed to prevent you from working on it, even if it is just symbols stripped etc, but more than likely signed, cipher, or obfuscated). Why does not it work, well you'll never figure it out because you won't ever be able to isolate the problem, are the bad, not really compatible, is it software, is anti-tampering controls you are not aware of, ...
For stuff from the early 2000s thru the teens the answer will be simple enough, replace entire systems like engine management and body modules with something after market. The CAN bus signalling to talk to human interfaces can be worked out easily enough. Collectors and purists will have to just 'get over' it not being totally original. The concourse guys that go wanking about replicating the style of zip tie the factory used to secure the wire harness will need to take a Xanax or something.
For newer stuff, I think it is going to have be all 'resto-mods' or they won't survive at all. Because as soon as you replace the ECM or body module, so goes the dash gauges and controls, the all the touch controls, stereo, entry sensors, etc. I am sure for popular models that lasted many years without major chassis changes you'll see whole kits replacing all the dash components, thru the door handles, etc that fit 2025-2028 Tonale or whatever. That will be the only realistic open for the Sunday afternoon in the garage guy who isn't absolutely made of money and wants to keep his "Classic" alive in 2050.