Equity is negotiable just like salary, and if supply of developer labor increases with the same or less demand, you'll get less equity just like you will get less salary.
I can't believe the person you replied to thinks that they're going to get some magical more amount of equity because you can hopefully do more with fewer people. That's assuming the entire business landscape doesn't also change with AI, disincentivizing so much investment in companies in the first place because someone else with AI can create a competitor in a shorter amount of time...
