PS1 games were still produced up until about 3 years into the PS2s life. The last 2 PS2 games were just released a few months ago. They are soccer games.

Saturn was LONG dead before PS2 and Dreamcast had a few Japanese exclusive titles released every year up until last year by NG Dev Team and a few other obscure developers. DC was long dead about a year into ps2s lifespan, in the US at least.

N64, I couldnt tell ya, but maybe they had a game or two released around ps2s launch date.