Because she's extremely careful, and decided she didn't have enough to make a conviction stick.

Yet.

Give it time. She's an excellent prosecutor, and she's doing her job extremely well. She's going after the people who are easily the most provably guilty first. This is a broad, far-reaching infestation of corruption and treachery, and I think she and Jack Smith are only getting started.

It would be a lot more difficult to indict a sitting congressperson on something like this, particularly since these can be a plausible argument that whatever they were doing could have simply falled under their official duties.

I think it's a good move to first go after Trump and the people in his inner circle, because if that conspiracy can be proved in court, it's an easier lift to then go after the Senators and Representatives who aided it, because one jury already found the conduct to be illegal (and thus not protected in any official capacity).

complete missed opportunity, probably had something to do with "resources" and "big fish", which to be fair, if I had to choose, gotta take the head off the snake, I don't know if anything stopping her from filing charges at a later date