In the US, retail investors have been allowed trade after hours since (Googles...) mid-1999.
[0] https://seekingalpha.com/article/4453440-after-hours-trading
I'm a regular Joe (in Canada no less) and my discount brokerage lets me trade after hours with no extra verification or fees.
It's only the regular Joe's that are not allowed the priviledge to trade at all hours.