I mean, I wasn't impressed with Obama, but I did vote against Trump every time. The reason that Trump won is because Americans are terrible at spotting propaganda, are racist, worship the rich, can't tell the difference between tv and reality, and what an instant gratification economy and Trump promised that. They would rather go along with the lie they want to heard rather than the truth they don't want to hear.
Putin and many other people saw they could use Trump to further their ends. That also includes Israel and the billionaire class. A lot of money got pumped into marketing Trump. Putin's been backing Trump since his bankruptcy problems and he was just a way to launder money, but when Trump was slighted by a Black man and decided to run for office, Putin saw an opportunity to divide America. When Trump won, he saw an opportunity to take Ukraine.