This is not (harmful) discrimination. Ceteris paribus, people with financial obligations are less fit to found a startup.
I have a wife and two kids (both under 5) and a big mortgage. I pay myself barely enough for us to get by (the lowest salary that I've ever earned). The difference is made up in savings and my wife's occasional consulting work. I'm the lowest paid in the company.
The cost of failure is so much higher, which simply means you're far more driven to succeed.
That said, older founders are also more likely to have access to capital, so of the kinds of discrimination I worry about in Silicon Valley, age discrimination is lower down on my list despite my salt-and-pepper beard.
Calling it discrimination is a bit odd though - It smacks of entitlement. But investors might want to consider these factors.
You've made a pretty extraordinary claim here; have you any evidence to back it up?