PS5 and the XBox successor will be running a custom AMD 'Navi' GPU or APU. AMD 'Navi' is expected to debut at retail sometime at the end of Q1 next year so I can see SONY & MS waiting for it to mature a few months before making their announcements.
FWIW, with the PS4 and XBox One most of the early games were remasters, etc... so it looks like it might be more of the same with this launch too. We'll see PS4 games drop next year and the inevitable remaster on the PS5 a few weeks later.
Side note: There's some chatter that Sony, MS & Nintendo want to adopt the cellphone hardware life cycle with their console hardware too. So expect newer iterations of the same generation but with more 'features' and a higher price.