Second, it is not "nuts" to use int, I would argue it's quite a bit more crazy to use rarely-supported 128-bit quantities when you don't need them. Your suggestion of "sint32" (this is not a standardized typedef, you mean int32_t perhaps) would be the same as int on most compilers today, and size_t is likewise very often 32 bits. Your suggestion is basically a no-op in a lot of places. Domain-specific areas like file formats or network protocols are a different story, as those have to be explicit about specifying sizes.
Third:
> someone’s language lawyering tendencies
I suggest you avoid passive-aggressive communication style and just say "you" instead of "someone". If you're going to criticize or give feedback, be direct. Don't vaguely tell me that "somebody" "might" have a problem.
Best regards to you, friend.