To be fair until Augustus there was a particular taboo in Rome of coming off as kinglike, being one guy and making a point of stepping on the Senate’s toes was a VERY fast way to get yourself killed, see also The Gracchi Brothers and Marius.
Romans hated anything to do with royal aspiration so much that one of their most sadistic pleasures was to watch the former royals of newly conquered lands be forced to march in the victory parade of the lead general of the conquest before being ritually strangled. It took being a literal child for the Roman public to hold back from gleefully jeering you for having been a monarch, nevermind being willing to ask for you to be spared from being killed.
Basically just imagine a several centuries long stretch of peak Robespierre paranoia about anything to do with potential plots on kingly aspirations and you can see why some guy deciding to take state business on himself, especially state business that can earn a lot of public support, would be seen as a dictatorship worthy crisis to the Roman Senate.