Bridgeless suspension forks
No, you can't broadly say "Bridged suspensions are stronger".  It's depends on many things, including the design of the system, materials used, build quality, etc.

As Batman mentioned, Cannondale's Lefty suspension is stronger than most traditional systems and isn't bridged, or even bridgeable.

Inverted, or "upside-down" systems, like the one in your photo, have other considerations as well, outlined in this question.  To your question, the thru axel keeps the stanchions bound together, preventing different rates of compression.

I think we will see fewer front forks with suspension bridges in the future and more inverted systems, as the technology trickles out to less expensive builds and the cost of manufacture drops.