The thing that keeps a 40-something like me from wanting to be in an SV type of startups relate more to priorities. I've been through the grind from the first bubble, and would rather not go through it again.
I'm talking about:
* Giving up salary for equity/options/signing bonuses. No thanks.
* Working stupid long hours that bring my effective hourly rate down to a fast-food restaurant manager's hourly rate. Because of this, I'd probably be flagged as someone who has "no passion" for what I do. No, I just like a balanced life.
* Working in a "frat house" environment. I've been there and had fun in those environments, but I'm past it, and prefer a more diverse workplace.
* Working in a VC-funded company - at least in my past experience - usually means the focus shifts from ramping up quickly vs. building value and/or a solid business model
It doesn't preclude the possibility, of course, that there may be other reasons someone might not be a good fit that age may predict.
* Candidate asks about overtime? Probably won't work late with us during crunches.
* Candidate won't take equity in lieu of a pay cut? Doesn't get at all what our mission is.
etc. etc.