That's longer ago than I thought, but still just within the decade, so it counts.
I admit it's a depressing performance by WotC.
Only a true D&D player would rules-lawyer the decade definition like that.
Sounds like a rollplayer, not a roleplayer.
I'm actually not a D&D player; I'm currently involved in Shadowrun, Blades in the Dark and Pathfinder 2. Despite that, I don't consider it very controversial to count a decade as 10 years.