If Arpaio does get the “damned goods” on Obama, it would likely open up the eventual floodgates to get Obama prosecuted. Some DA in the country would get the ball rolling.
If more of the facts are made public, those trying to ignore this will find it much harder to do so, plus those who would like to get on board but don’t want to be the lone person doing so, will find strength in numbers.
Just look at this thread - how many negative comments.
So for public figures it’s hard to publicly support a cause that is labeled “kook/fringe”. Even on FR there is much scorn and ridicule heaped on those who think it’s important.