This is an example of what I'm talking about. The reason the money is influential is because some people are naive and listen to the advertising/campaigning, which often misrepresents facts or only tells one side.

"There should be few limits on that..."

I'm not discussing limits, other than a basic citizenship test which all non-birthright citizens already take. The majority of this should be handled in schools. There's really no reason not to have the test.

"They are more than capable of sharing their life stories, policy preferences, needs, and other things same as anyone else."

Not if they are being manipulated because they don't understand the system or investigate claims. Then you end up with policies built off of lies and misrepresentation.

If you want an example, look at the PA ballot question from a few years ago about retirement age for judges. They manipulated people by rewording the question. The integrity of the system and the strength of the country is dependent upon knowledge citizens in a democracy. To make this clearer to you, here's another example. Why is consensual sex with a minor a crime? It's because the minor is consider to be incapable of comprehending the totality of the situation and giving informed consent. The same can be true of electing people. How can you give your informed consent for a person to represent you on issues if you don't even understand the basics of it? This undermines the general public's right to be governed by a fair and effective system.