It depends. There is a site setting that allows you to disable safe mode, which is helpful for the gated topic component and other components/plugins users shouldn’t easily disable like that (advertising, guest gate, …). But while you are logged out, that would also make using safe mode more difficult for admins. I think they can still enable it using admin-login.
For this plugin, I doubt safe mode helps. Safe mode disables only the front-end part of plugins, and this plugin in 100% Ruby. So I don’t think disabling JavaScript customizations is any help. This fact makes me a little skeptical about the plugin, as does the fact that it includes an about.json file as if it were a theme component. But in the end, everyone is responsible for the code they install on their forum.