* done for optics, to look like growth or doing well, or just to have their name out there.
* to fill the pipeline for future needs
* to assess the hiring market, for planning
* (for reasons mentioned in article) to light fire under current employees, or see how replaceable they are
* only for a serendipitous unicorn hire, not commodity developer
* for training in their hiring process
I know all these are things that happen in general with startup job posts, though not necessarily on HN.
None of those reasons preclude "responding", but responding doesn't solve the real problem, it's only a PR sugar coating on it.
An example of disclosure on the unicorn hire one would be to simply state the truth about it. That's fine, so long as you're not pretending to grow. It could even be good optics, about hiring standards.
Disclosure of some of the other intent would preclude it (e.g., probably nobody is going to state the goal of threatening or replacing current employees). Maybe those posts shouldn't be done at all, or maybe they can at least say that this is a speculative post, not for a currently open position.
I'd say job posts have to be truthful, and it's by default implied that they actually good faith intend to fill the position as described, in a timely manner, and that interviews will only be conducted in good faith. If the default isn't true, they should disclose that.