This could happen when you're playing other games. It's possible your PS5's internals have built up a lot of dust over time, and that the liquid metal has been completely worn.
The best solution really, is if you can handle fixing it yourself with the proper tools, then by all means, but there is always the option to send it to someone who can fix it for you.
This happened to me a while back where my PS5 shut down without any overheat warnings around 30 minutes into a game (using either Astro bot or Stellar Blade for example, and GT7 is included too), and after I got the internals cleaned and the liquid metal replaced, it's worked perfectly fine ever since with no shutdowns.
