Depends on what you use the computer for, for gaming, maybe you're right, idk. I personally use the computer for 3D modeling which mostly relies on the GPU.
I've recently built a computer with the latest gen GPU and got a nice 12 gen i7 as platform for it, the GPU is from 2025, but the CPU is like 4 years old.
The thing is, I could have gotten a much older CPU haven't I found the 12th gen for the same price. If I could just upgrade the GPU and ram on my old laptop I wouldn't have bought a whole computer.
Besides, buying a laptop with 16GB of vram would have been much more expensive than a desktop.