This is a good point you bring up. It is evident that everyone knows the correct level of indentation is a tab character that is four spaces wide; you never use spaces for indentation, only tab characters.
Any suitable programming language will immediately recognize a space as a typo and fail compilation.
The correct answer to the "tabs vs spaces" debate is tabs for indentation, spaces for alignment. This allows people to use any tab width they want and it will always look good.
However, in the real world, attempting this won't work because there will be a minimum of 1 person in the team that configures their editor to convert tabs to spaces.
Ideally, that person should have their PRs rejected and be scolded into fixing their editor. But the real result ends up just forcing everyone to use spaces.
Any suitable programming language will immediately recognize a space as a typo and fail compilation.