Okay, so this discussion is worrying me a bit, so I did some test renders for a frame of a big animation scene I’m working on (over 1 million polygons, lots of 1K textures, only one directional light source but it does use ray tracing in Eevee and Path Tracing in Cycles). My current laptop has both an NVidia RTX 3060 card (when plugged in at full power) plus an AMD CPU+GPU for when it’s unplugged from the wall and I need to save a bit of battery. I got the computer back in April of 2021, so there is a possibility that newer laptops are generally faster for CPU-only rendering just because they use newer parts.
Naturally, CUDA + my RTX 3060 renders the scene the absolute fastest on Eevee with ray tracing on, at an average of about 10-15 seconds per frame, but HIP with both my AMD CPU and GPU at the same time renders at a respectable 30-35 seconds per frame.
Interestingly, I get a good middle ground if I switch the render engine to Cycles, only use it on CPU (no GPU), lower the final samples to only 8 (as opposed to the default of–gulp–4,000 samples), and turn on Denoise without touching any of its default settings–the result is only 25-30 seconds per frame for an arguably-more-realistic path traced render! Of course, Cycles is significantly faster when I use CUDA + an NVidia GPU, but you get the idea.
So yeah, at least in my case, rendering in CUDA is noticeably faster, but HIP and AMD CPUs+GPUs also render somewhat-unoptimized scenes at respectable times, to the point where you have to ask yourself if over-paying for an NVidia card in 2025 is really worth it just for somewhat-faster render times in Eevee with ray tracing on–especially since, if you can figure out a way to get away with extremely low samples in Cycles and the Denoise function, you could get some surprisingly-fast renders just on a CPU, maybe even feasibly use Cycles to render long animations!
Finally, of course if you want TRUE real-time rendering, game engines are your only true options, not Cycles and Eevee. Godot is perhaps the most lightweight one out there, whether you set the graphics quality to Compatibility, Mobile or Desktop/Console, and doesn’t care what GPU you use it with so long as you have any relatively-recent GPU at all, and for large teams, Unreal Engine 5 seems to be a dream engine for bigger productions (e.g. The Amazing Digital Circus episodes are rendered in UE).
All in all, while having an NVidia GPU is certainly nice, it really isn’t the end of the world if you have to settle for any other GPU, especially once you learn and get better at optimizing your textures, file sizes and renders.