Ron Paul reached the maximum number of people that could be reached with that strategy [...]
Apart from mere assertion, what reason is there to think that the number of people he reached was the maximum that could have been?
Because the "innovators" and "early adopters" are always a very small segment in any market. There just aren't enough of them. The early and late majority account for something like 66% of the market.
The hardest part is switching your focus to go after that majority, while keeping your early customers happy, which was obviously the problem with Rand. If libertarians realized that he was doing this and would have donated the way they donated to Ron, he would have had a much better shot. He may still have lost because Trump, with the media's help, messed things up for everyone, including Jeb who was the favorite and also had an establishment strategy.
The early majority, also called "pragmatists", are scared away by big changes. They don't like anything too disruptive and are looking for incremental improvements only. They look for things that can neatly fit into their already established routines. Innovators and early adopters are the ones looking for revolution. To sell to the early majority and late majority, you have to package your message a certain way.