In the grand scheme of it, I haven't worked with that many, but every founder I have had the chance to work with has cared about sustainability. This is way more speculative, but I believe that sustainability goes out the window in favor of quarterly wins when the (co)founder steps back from their role and they transition to a non-(co)founder CEO and such.

I guess we could interpret that as the cofounder cares about sustainability for as long as it takes to hand off the bag.

Once the founder takes VC funding, it no longer matters what the founder wants even if that is true.