Why do people keep saying this? Firstly, it's simply not true...there were lots of people that disliked him. He scammed desperate working class people through his own university, he bankrupted his own casino not paying contractors, employees and investors in the process, locals of Aberdeen did not want a giant golf course on their natural landscape, he already had a dozen accusations of sexual misconduct and even assault plus he would sue anyone he could just for the sake of it.
And secondly, lets just say for your sake, it's completely true and everything I just stated is a lie, literally everyone who runs for office comes out on the other side widely disliked. They run on promises and hope that they can't deliver.