alt Hacker NewsC uses pointer casts all over the place to fake generics. If you don't have that (in Pascal or MODULA-2) then life becomes very unpleasant.
There is a quite a bit of C code that makes creative use of the size of allocations. For example linked lists with a variable sized payload. Again one of the things that would prevent a C programmer from switching to Pascal.
I don't expect the Zig user base to become larger than the Rust user base any time soon. But we have to wait and see, Zig is quite young.
Same tricks are possible in Modula-2, Pascal, Ada, if fake generics count.
Creative use of the size of allocations are also possible in those languages, the BIG difference is that they aren't the default way everything gets done.