Well, you see, most OSes today aren't written in ASM. Their native libraries are C, so you have to interface with those libraries if you want to utilize them and their features.

You can certainly write your own TCP/IP stack with raw sockets and directly interface with the NIC, if you like. But at that point you're both reinventing the wheel and bypassing the entirety of the OS, you might as well just write a forum exokernel.

Most developers don't consider utilizing a library in another language as "cheating". Popular and core Rust, D, C++, Python, nodeJS, etc libraries do this all the time.