[RetpolineDrama]

>Any alien race with technology to reach Sol will also have superior technology to defend themselves.

Actually I was surprised to find this isn't _strictly_ true, but it is likely.

One possibility is other solar systems (far away) with a different blend of materials that make certain advancements "easier". One hypothetical example is a far away solar system having high quantities of "exotic" stable super-heavy elements that make things like FTL possible.

In such a scenario we wouldn't discover it because it's not naturally occurring in our solar system, and we wouldn't stumble on it until we built a large enough particle accelerator. So another race could be _way_ ahead of us with respect to FTL, but way behind us in things like material science or computers. Imagine if their solar system was completely missing say... silicon.