A trade deal with the US is going to put the US first and be quite bad for the UK in more ways than it is good. Doing a deal with Trump, in particular would have been particularly bad unless he was to break the habit of a lifetime and go for something that is equitable. Unlikely.
The comparisons between Trump politics and Brexit politics are a very close match.
Same supporters, same funders, same politicians, same political tactics, same analysts and consultants, same crusade against wokeism, same overplaying of the significance of items deemed to be sacred (the flag, the anthem, the monuments to slavers), same longing for a bygone era, same xenophobia (couched as patriotism), same trench warfare us-against-the-world mentality, same retreat into national introversion (couched in being "global" and the "best in the world"), same reluctance to pay into any schemes that make the world safer or more equitable, same climate change denial, same quest for deregulation at the expense of the environment, same quest for deregulation at the expense of health and safety, same tendencies towards authoritarianism.