Possibly. Depends whether you applies today's standards, or the standards of the time.
In absolute terms, terrible at Trump is, you could argue that most presidencies of the 19th century would have been worse... after all those presidents, in some cases, openly supported or openly tolerated slavery and, even after slavery was abolished, accepted or supported discrimination against blacks that went way, way, beyond anything you see today. Attitudes towards women would have been totally misogynistic by today's standards too. And as I understand it for much of the 19th century, corruption in elections was open and rife - only finally cleaned up thanks to general public disgust towards the end of the 19th century.
But on the other hand, most of those 19th century presidencies were also simply reflecting the standards of the day, and very often, they were making slow progress in improving things. To my mind, the almost uniquely bad thing about Trump is the way he's completely ignored today's 21st century standards of ethics and actually taken the level of Government very substantially backwards, towards what would have been common 130 or so years ago. So I would think Trump will have been the worst President by far if you measure by the common acceptable standards of behaviour at the time, but not if you retrospectively apply today's standards to all past presidents.
(For what it's worth, I think it's a totally unrealistic to expect people 200 years ago to have lived by today's standards, so it's much better to try to judge by the standards of the time. After all, who knows what things that we all think are perfectly fine and reasonable will be viewed with utter disgust by almost everyone in 100 or 200 years' time).
