tarzip

That's what safeties are for! We already have a lot of engineering around making elevators safe. TLDR the elevator will clamp on to the rails to slow the free fall. Neat info below on snapping elevator cables and some of the things that would help you. https://science.howstuffworks.com/science-vs-myth/everyday-m...

You certainly should worry about the possibility of zero day attacks either when using FOSS or a proprietary solution.

If the provider of a proprietary solution stops offering it you might have no easy path of migration where as hypothetically FOSS solutions are easier to self host or find a new hoster for (and thus reducing the cost of a potential migration)