Trump’s absolute maximum positive approval rating is 65% because the hard core left of this country and their sycophants (now about 35%) will “strongly disapprove” of him no matter what he does. If he somehow managed to cure cancer and send every single American a check for $50,000.00, 35% of the country would still strongly disapprove of him.
So 65% is running the table. Then you have to consider the dishonest nature of most modern polling and the effect of agenda driven fake news.
The bottom line for Trump is anything in the 40’s should be considered doing an excellent job.
Don’t believe any poll until you can read its internal breakdown of participants: Repubs, Dems, Inde.
IIRC, Obama never polled above 45%, yet he was reelected to inflict another 4 years of destructive policies on us.