They were planning to use Cambridge Analytica to make it happen /s
In all reality, the common public is probably indifferent to his running, at this point, and I believe this current series of events hasn't changed much.
It was easy enough to see Trump coming ahead of time though. He’s been talking on and off about running for a long time, and that speech more recently where he called the Chinese “motherfuckers” in particular should have made it clear that what he might do could be effective. Once you accept that he’s running and what his style would be like, it’s easy to see him getting the nomination.
It’s not easy to see Zuckerberg getting the nomination under pretty much any circumstances.