How so? I find it much the same to other templating engines like Jinja, though I'm definitely not a fan of the syntax. But that hardly matters anymore with LLMs.
I think it's a combination of text templating + yaml (which is whitespace delimited). When templating html with Jinja, it's not a big deal if the indentation isn't right. In helm, best case you get a syntax error, worst case you end up overwriting keys and producing something syntactically but not logically correct.