The RAM is clearly VERY user upgradable, at least compared to how damn difficult it was to upgrade storage on the 2014 Mini, which I also did.
If I could have just taken off the black cover and been able to upgrade the storage on the 2014 mini, it would have been a cake walk.
This is VERY user upgradable, but like all things, if you take it upon yourself, you also take the liability that comes with it.
I upgraded the turbo(to IS38) on my 2017 GTI, but that doesn't mean my warranty is void, it just means that if the turbo lets go and ruins the engine, I wont be getting a new engine. But if the infotainment system breaks or the suspension needs work, it will be replaced under warranty. Its similar with this mac.