The difference is, that you could just continue using XP until Win7 was released or continue using Win7 until Win10 was released. Win10 will reach end of life next year and then the only supported Windows will be Windows 11. Vista or Win8 were never as forced as Win11 is now.
The last times May 4 was on a Thursday were 2006, 2017 and 2023. The Core 2 wasn’t released until July of 2006 so I’d guess the correct year is 2017, but even then the hardware was already pretty dated. For reference, in 2017 the first generation Ryzen prozessors and Intel Kaby Lake (7th generation Core i) were around.