It's really more of a computer than a car. The MCU1 hardware is actually from 2011 which is ancient. When I had my MCU1 replaced due to failure, Tesla installed a new one and reset everything. It was maybe a little faster, but barely. Yeah, we can say Tesla should optimize their code better, not bloat it up with features we don't want, etc. but in the end there's not much we can do about it short of hacking it to strip out everything we deem unnecessary. I chose MCU2 instead, even if it cost me $1500. As it directly affects how I interact with the car in a meaningful way (I don't need the games or Netflix either), it's not an upgrade I've regretted at all, and it will make the car easier to sell when it's time to move on.
I don't know how MCU1 performed in 2012, but it's a mystery how well MCU2 will age. I expect it to provide decent performance for the rest of the car's life, however.