Having a small group to influence is bad for democracy is what I thought you were saying. That implies having more people to influence is better for democracy. If that’s not what you were saying, I apologize for misconstruing, but I see that mindset soften enough, and to me it seems like a fallacy. You just end up with a run away election industry and high paid propaganda specialists, the normalization of domestic propaganda campaigns, the unraveling of social cohesion as large swaths of the populace become convinced the other half are nazi’s, fascists, communist spies, pedos, Russian assets, etc… every new election a bit more polarizing and traumatizing to the national psyche than the prior. Yay, democracy!
My point was that a larger and more diverse voting pool makes any single influence attack less effective.
I don’t know why a smaller voting population would preclude any of the things you mention.