To me it makes sense. If you don't know what endianness is, it doesn't make sense that a program you write in one programming language works for one target but doesn't work for the other.
I think endianness is the footgun that Zig is solving, rather than Zig being the one introducing a footgun when you deal with endianness.
> If you don't know what endianness is
It is not feasible for someone to write endian portable code in a language like Zig without understanding what endianness is imo. Regardless of how they change @bitCast there will be other cases that break this like doing @ptrCast + @memcpy.
Also this breaks currently written code that is endian portable and uses @byteSwap like it is done in most other programming languages that do these things.