If someone steps on that, they are probably going to go through. The membrane looks solid, I don't know if with heat or age if a hole could form. When we reroofed my garage, we didn't leave any holes like that. Any soft spots got resheeted in plywood. Small gaps are probably okay, but that looks like 1 foot+
I agree. The manufacturer of the membrane would not have designed their product to operate over a gap like that. This to me would be the cause of accelerated wear and tear.