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The main problem are the OEM vendors, regardless of what operating system they use, they always try to make they system experience "unique".
This is what I miss from the 8 and 16 bits days. Since the computers and OS were most of the time from the same vendor, there was no OEM differentiation stuff.
The differentiation was achieved by having different types of hardware+OS systems in the market.
PC OEMs brought the cost of computers down, but now we have crapware everywhere.
I guess it is hard to have both.