You're missing his point. Defaults matter. A huge majority of users (80%?) never change the defaults, often for good reasons.

A minor usability investment on the part of 1-2 git developers would prevent thousands of hours wasted by newbies and perpetual intermediates (https://blog.codinghorror.com/defending-perpetual-intermedia...).

A feature like undo is never going to be implemented as a core thing because there are too many instances where it's not clear what it should do.