How can it possibly be beyond reason to question the morality of Trump? Evidence ABOUNDS. You don't even have to dig for it. It's right there in his lifestyle, his business practices, and his general demeanor.
It's not the question that is the problem. It is the offensive way the questions are delivered -- as declarations of absolute truth,when in fact, it is the poster's personal opinion and judgment -- that is the problem. It is also the presumption that being an armchair keyboardist is a qualificatiion to judge, based on hearsay, outdated sources or political talking points rather than objective research from actual witnesses.
Many people go through life believing that their personal opinion is the same as actual fact. It is a mark of maturity, and far less offensive to others, to learn to express one's point of view objectively, or at least to admit it is an opinion or an impression you have, not something you truly know anything about. You weren't there; but God was. He alone is the judge of people's souls.