Small reality check: go and look how easy it is to upgrade the average Android phone. Once you found out you can come back and complain about lazy users failing to update their devices using official or easy updates that almost always don't exist; or using root access that generally requires reading pages upon pages upon pages to get. If it's possible at all.
And of course if you belong to the 1% or so of people who have the required skillset you have to give up your warranty (according to the manufacturers at least, I for one would love to see this tested in court).
The situation is slightly better on iOS, but even there updates are only available for a fraction of the useful life of these extremely expensive devices.