"Yooo, I feel ya. I had a similar issue with Blender on my 3090, but it was mostly due to the rendering settings. Try checking your CPU usage and see if it's pegged, might be a bottleneck there too"
"yep, same here, 4090 isn't the holy grail like everyone thinks it is when it comes to rendering in Blender, especially if you're working with high-poly models and complex scenes. CPU is still your bottleneck, sadly. Have you tried tweaking your render settings or using a different render engine?"