You still get 4 years with 10.

The Intel 8th gneration was introduced in 2017. So people who bought a computer in 2016 can still push it to ~9 years of service life, which is pretty good for an average Windows computer if they manage to do it. I imagine your average Windows consumer will have replaced a computer once already in that span once all the installed crap has stalled the computer to inoperable speeds.

This honestly doesn't really strike me as a major issue. Especially since smartphones have like less than three years of security fixes on average.