Chief trails will stay open. They might close "Sea to Summit" (originally known as "Upper Shannon Falls" trail, before the gondola). I can't imagine Sky Pilot access getting restricted either.
Security is indeed big ? According to
Squamish Chief "
An individual climbed the tower with the right tool with great speed and cut through the cable and brought the system down". There is image on security cameras, probably mounted on Towers. Culprit likely drove on Mamquam main and up Indian FSR, then walked over with whatever tool was used. They need security cameras there, not just at gondola base. But I agree, until they catch the culprit gondola should not be reopened.