Hmm - that's not actually a very good example, because it's taking place next to a map border, and ships generally try to avoid that, so what we're seeing there aren't their "normal" behaviors.
Passive AI sure make things a lot less fun. It's ok when your ships are cautious and don't overextend, but they remain passive and even retreat while the enemy flameouts or overloads (or both). Orders (full assault included) don't help.
I'd love to see specific examples! It's tough to say one way or another w/o seeing something in action; there could be a legitimate reason to hang back. And, as much as I can understand being frustrated when an AI ally occasionally refuses to help in just the right way, it's *way* more frustrating when their behavior causes you to lose ships, especially off-screen. So, even if ships minimizing risks can carry with it some downsides, I think it's a very worthwhile trade-off.
I will say that "full assault" and "eliminate" absolutely *do* make a huge difference - it's possible that there are some cases where they don't result in desired behavior, but I think that's quite different from "don't help", which implies they don't do anything. In my experience, they work quite well - especially Eliminate, which I tend to use a lot - though of course bugs are possible, and perhaps there are situations where it doesn't work as it should.