Two major issues. One- indent only code is nearly impossible to find bugs in. I've seen teams of programmers look for weeks for the source of an issue, it ended up being 1 line that used a tab instead of spaces. Indentation fails because of such issues.
Secondly, you can't copy paste cleanly from the web with an indentation based language.
Either of those is a disqualified by itself. Both together make it such a brain dead choice nobody should even look at a language that uses it