In practice the problem containers solve is to bundle an application with its environment so that it will work the same on the developers machine and in production and in five years time when the servers are replaced with new ones running another distro.
The WASM world doesn't have most of the pieces of that puzzle and WASM itself is quite irrelevant. Say we standardized on a sandbox running x86_64 VMs under Firecracker, with the proper sandboxing that would work just as well as running WASM. You might say that WASM is portable, x86_64 assembler is not, to that I would counter that ARM (and probably RISC-V too) can emulate x86_64 faster than they can run WASM. So what's the point of the WASM piece of the puzzle?
The WASM world doesn't have most of the pieces of that puzzle and WASM itself is quite irrelevant. Say we standardized on a sandbox running x86_64 VMs under Firecracker, with the proper sandboxing that would work just as well as running WASM. You might say that WASM is portable, x86_64 assembler is not, to that I would counter that ARM (and probably RISC-V too) can emulate x86_64 faster than they can run WASM. So what's the point of the WASM piece of the puzzle?