Ah I think I see the confusion.

I was saying that there’s nothing, within our current physics, that is not efficient than a matter/antimatter reaction. You get 100% of the energy. Whether or not it’s useful energy is another question, and I’m doing some hand-waving around the topics of containment, manipulation, etc. However, nothing we know of is a more efficient use of matter to generate electricity. Not fission; not fusion; not radioactive decay. If we could wrap a black hole in a Dyson sphere and capture Hawking radiation, it’d still be less efficient than M/AM annihilation.

I was saying that - barring a magic technology such as capturing usable energy from quantum fluctuation, saying ST has a form of energy production that is a matter-based energy production that is more efficient than M/AM annihilation would violate our known laws of physics, because introducing a hydrogen atom to an anti-hydrogen atom is 100% efficient and costs nearly nothing to effect.

ST is full of magic technologies, and carrying around a bunch of AM as part of a way to play Mozart in the ready room is really dangerous, so - maybe they use it a bit, but they rely on more stable, less dangerous energy sources like dilithium. Anyway, trying to mix hard science and Star Trek is a dangerous endeavor. ST is more hard-sciency than the Space Wizards in Star Wars, but there’s still a vast amount of speculation required to make things work.