Dunno where you got that number from but it's half that. Tokei says:

  ===============================================================================
   Language            Files        Lines         Code     Comments       Blanks
  ===============================================================================
   Zig                  1298       711112       577946        57772        75394
   Rust                 1443       931232       737485       114373        79374

So it's 28% more lines of code (not comments/blanks).

Rust is mostly ~20% bigger. Except comments. Where they basically doubled... what's with that?