This would not be a smart move. Trump gives up all his leverage, the wall never gets built anyway, and a bunch of Republicans in the House and Senste who never wanted a wall to begin with can continue to lie their asses off to their voters and pretend they do.
In another week or two McConnell will have enough GOP votes to override a veto. GOP voter turnout will crater in 2020 and Trump won’t be reelected if it becomes clear the GOP doesn’t want a wall either. So much of this PR battle is POTUS trying to hide that fact.
What the GOPe wants is a funding bill with no wall money and a executive action that will be tied up in the courts. My guess is POTUS does that since the alternative (a veto override) is much worse optics for 2020.
"...President Trump gives up all his leverage..."