IMO, in most tanks they are already there, and are not just bacteria. Algae and diatoms also serve the function of taking up space where dinos may want to take over perfectly well, for example. On the bacteria side, adding more on a regular basis might possibly help keep the right strains present if they are amongst what you are dosing, but it might also be like adding 5 gallons of gas to your car every day, without knowing whether it will fit in the tank or not.
Again IMO, I think displacement/outcompetition of dinos is often an effective plan, and that can be accomplished many ways. Adding bacteria may be one of them, but isn't the one I generally recommend anyway. Keeping nutrients higher is one of them.
Cyano has different needs and different ways to deal with it. I'm less convinced bacterial competition will be successful there, but in some scenarios it may be.
Thank you Randy . Continually trying to learn which is why I love this hobby.