Hideaki Nishino confirms the PS6 will launch "on schedule"

[BraLoD]

I would guess 2028.
PS5 released 4 years after the PS4 Pro, and 4 years after the PS5 Pro will be in late 2028.
PS1 to PS2 to PS3 had a 6 years gap each.
PS3 to PS4 to PS5 had a 7 years gap each.
It looks like it's time for the 8 years long generation.