>>1016212
When creating stylized scenes like this, it would be best to switch over to Eevee, I'd say. It's less photo realistic, but much faster than Cycles generally speaking. Also Cycles default render settings aren't the best. You can reduce the sample amount and noise threshold significantly without any visible loss in quality. My first guess would be, that the mentioned settings were way higher than necessary.

If I am not mistaken, the default sample amount is 4096. You can reduce it to 1024 or even 512.
For the noise threshold the default is at 0.100(?) which is fine, but you can increase it to 0.2 or 0.3 if it really takes too long and enable the Denoiser. The Denoiser is a bit tricky tough. If you have many details in your textures, they can get eaten by the Denoiser, so some simple compositing tricks would be required to bring them back.

Am I assuming correctly, that you are on a notebook without a built-in GPU?

>>1016221
>i5 13600KF 3.5 GHz, RTX 4070, 32GB ram
That is a beast, what are you talking about? xD I dont think a new PC is necessary to be honest, unless you really want to spend 10k on the newest hardware just to reduce the render time to 1/4. It would make sense, if you are going to mass produce blockbusters. :D
Studios also delegate the rendering to render farms, but if you do short clips, local render is totally fine in my opinion. And yes, you can use multiple instances of Blender (eg. rendering on the first instance, while working on a different project on the second instance). I did that without any issues. To be fair, I didnt render processing heavy images, but still it worked out very well.

As to anon above, try tweaking the render settings to your needs and check the system settings too (see image). For RTX you want OptiX enabled. And obviously your installed graphics card.