"A two-front solution could be really great. We need developers to write their best resumes, and we need employers to write their best job descriptions. Having them 'speak the same language' on concise accomplishments, metrics, technologies will make more automated matching a lot (a lot) easier." - 100%! This is the market place that Linkedin has been trying to create - but hasn't worked very well, right? They have largely solved the problem of structuring the resume data - which is definitely useful, but I don't see much of that on the job description side. The matching algorithms can only rise up to the level of quality of the input data - the resume data, and the job description.
There are similar problems in the dating industry, but mostly you can be sure both parties are putting their best efforts for creating better input.
I think honesty is also a critical part of the equation. And if the Linkedin or indeed could encourage both sides to reveal what they value deeply - that would things more useful. May be a few why questions rather than just checkboxes and drop downs that can be filled quickly. Candidate: Why is remote working important for you? Job poster: Why is a self-starter important for you? That would help bring out the uniqueness for the candidates and helped the matching algorithms.
Will look forward to seeing your product on Show HN - best wishes!