> this just isn't the kind of professionalism needed for a serious project

I actually think this gets to, but steps over, the core objection: traditional "hacker" mindset vs VC "growth hacking" mindset.

> And I am sorry, but adoption and reaching critical mass is an important part of a serious programming language.

Why? Why can't he create a language with exactly the kind of purity and ideology he wants, broader adoption be damned? Why must everything optimize for user growth and mindshare?