Security isn't just about your data. It's about the security of an open web. Having one rendering engine that controls everything is not secure.

It's actually the beauty of open source that we can align on a few primitives that are reusable in several different contexts to build radically different product experiences and world views. If you think of the phylogenetic tree of software this is exactly what you want to happen.

“Resilience” conveys your meaning better than “security”, and it calls to mind more relevant interventions.