And by email from Sony at the end of the year, I believe. 

That is specifically for the year, but you're right. 

You can see the last games total time on the PS App, dunno if there is a full list somewhere there.

You can also use a site like Exophase to check PS4 and PS5 game times too.

There's three ways to tell your game time.

From the PS App on phone though limited to recently played.

The main PS5 Home/Hub screen where it will show you individually (though it seems not work with PS Classics at least from my experience)

Then your profile on the PS5 where you can re-arrange by most played under games where it will show you your entire list.

You can use this site.

I checked my profile on PS5 now.

My top 5 (out of 317 games logged)

GT Sport: 7,321
Minecraft: 1,473
GT7: 1,264 (664 on PS5, 600 on PS4)
Death Stranding: 475
No Man's Sky: 411

Thank for the replies guys!

Don’t have a PS5 of course but of all-time on all PlayStations it’s probably a boring top 3 consisting of three Guitar Heroes.

I don’t think I still have a way of knowing but I guess the order would be;
1. Guitar Hero 3
2. Guitar Hero Metallica
3. Guitar Hero World Tour.

Yeah I had a real addiction for a short while there. Obviously I played other stuff, but things like the story of Uncharted 2 and Crash on PS1 are bound to have been much shorter.

7,321 hours. Wow. That's the highest I've seen yet if you don't combine Fifa yearly releases. You're 1,200 hours of modern GT racing away from becoming a professional. You're top 3 games combined beats all of the gaming I've done over a decade. You, sir, win this thread 👏.  Amazing. 

I've only ever played PS1&2 games.
To take a guess, most played might be Ridge Racer Type 4, Okami and maybe Tekken 5 or FF8.
Except I forgot PSP. Phantasy Star Portable is probably second after RR4.