You're right about the flipside, PA could be more important to Trump than it is for Biden (if Biden flips another similar state back instead).
I'm just dreading an election post mortem where we find out the Biden campaign diverted resources away from PA to flipping TX or a similar quixotic goal.
As I look at it again, PA really is the big one. You can pretty much give all the toss-ups to Trump, but if he loses PA, he loses. Biden can lose PA and still have a good shot. If Biden wins any one of FL, AZ, OH, NC, or GA, Trump can have PA and still lose.
If I were Trump, I would make sweet love to a fracking pump on national TV with a Steelers jersey on while handing out $100 bills. PA is his only chance.