Have you seen how Trump supporters treat other politicians? Trump gets a pass on anything because he's on "their team", opponents are under a hyper-partisan microscope where even reasonable normal behavior is criticized.
That's completely normal in partisan politics. This stuff occupies the same headspace as cheering on a football team for most people.
Which is to say, when you make being a member of a political group part of your identity, you are inclined to defend it as you would yourself: with irrational non-objective gusto.
Of course people are always going to use social media for ammo, I just think the era where politicians can reasonably expect to curate a public image that's wildly different from their personal lifestyle is essentially over. And honestly that might be a good thing -- much like mutually assured destruction with nuclear missiles, if every politician knows their opponents can dig up bad stuff about them easily it might elevate the discourse since low blows will lead to a vicious cycle for everyone
Which is to say, when you make being a member of a political group part of your identity, you are inclined to defend it as you would yourself: with irrational non-objective gusto.