From a different topic in the board, but apropos.
Also, bear in mind that in the past half-century, incumbent presidents have lost just as many times (4) as they’ve won (4). Ford, Carter, Bush Sr. and Trump lost. Reagan, Clinton, Bush Jr. and Obama won. So a 4-4 record suggests that incumbent advantage doesn’t mean all that much anyway.
Incumbency as it relates to the White House looks like a complete toss-up.