If the beavers banded together and tried to exterminate humanity, they wouldn’t get as far as humanity would exterminating beaverkind. That’s domination: exerting your will on those around you to their detriment and not being deterred by their resistance, no?

I don’t think that’s a fun competition or nice thing to consider, but there are few animals that could come close to beating us in that regard. Ants, termites, and bees are the first that come to mind for me, but there are probably other possibilities.

Plants, fungi, and bacteria on the other hand… I don’t think we could really expect to win against the most ubiquitous examples of those.

Now explain why somehow our most important trait makes us dominant from a biological point of view.

It allows us to accomplish far more than would normally occur based on our biological limitations.

Your problem is trying to argue based on an academic definition (that is not universally defined) against the common usage of the word dominant and doing a piss poor job of making that clear. Like when someone uses the lay version of theory and then arguing against it based on the scientific definition of theory without making it clear which one you are using.