The problem of leading spaces not changing their size can be solved through programming.

Those programmers who have such a problem and need leading space to be rubbery, if those programmers are worthy, will solve that problem instead of complaining that everyone should adapt to them.

The use of tabs is detrimental to code bases. Whenever tabs creep in, invariably people use different tab settings and make a dog's breakfast out of the code.

Code exhibits indented sub-structures that are internally indented, but not themselves not aligned to a tab stop, but aligned with something. One kind of example is something like:

  function_name_of_random_length(lambda (a, b) {
                                     if (a < b) {
                                         indented();
                                     }
                                 },
                                 arg2);