I’ve written various applications on top of FFmpeg but never looked into encoder technicalities, so I don’t know if and why GPU encoding has fundamental limitat

I’ve written various applications on top of FFmpeg but never looked into encoder technicalities, so I don’t know if and why GPU encoding has fundamental limitations. I heard nvenc has vastly improved on RTX cards; I’m still rocking an old GPU so can’t verify that, but presumably that means there’s no fundamental weakness and GPU encoding is just playing catch up?