Wrong - https://en.wikipedia.org/wiki/2010s
The 2010s is the current decade in the Gregorian calendar that began on 1 January 2010, and will end on 31 December 2019.
The 2010s is the current decade in the Gregorian calendar that began on 1 January 2010, and will end on 31 December 2019.
Daily usage differs from that definition of course, but that's not the point.
>By your logic the year 2000 should be part of the 90's which it wasn't.
It was according to the gregorian calendar.
A lot of concepts in daily human lives get fuzzy near the edges. That's not a failing on humans, that's how language works. This isn't scientific or perfectly rational, yes, but neither are humans.
It's not an edge case though.