I suspect that's a very slimmed-down .config and probably only e.g. `make bzImage`, versus something like a Debian kernel .config with modules, headers, etc. A full Ubuntu kernel takes quite a bit longer on my 5950X, which is admittedly quite a bit slower than a 9950X but still no laggard. I'll time it and update this comment later...

ETA: After dropping caches it took 18m40s to build Ubuntu mainline 6.16.3 with gcc-14 on my 5950X, with packages for everything including linux-doc, linux-rust-lib, linux-source, etc. I'd expect the same operation to take about 11m on a 9950X.

It's also not clear whether OP used Clang or GCC to build the kernel. Clang would be faster.