Vingegaard had nothing to lose, there was no way he was going to lose 7 minutes (yet he kept looking behind nervously as if Pogacar could somehow close the 7 minutes any moment). He did have something to win, a nice stage (entirely without any risk for his yellow jersey). To do that, his only chance was to go full on the climb and try and break Pogacar there, he had 6-7km to do so. Not doing anything and almost going for a sur place was basically just Vingegaard telling Pogacar "No, I do not want to stage, please take the stage win".
It feels a little like a typical ending for the Tour, which was won by easily the strongest rider/team, but also an equally boring rider. I am fully aware the result is the only thing that counts in the end, so one can hardly blame them, but let's say as a fan the heart rate does not go up a single beat when watching Vingegaard and 'Jumbo-Sky'/'US Postal-Visma'/etc. Sort of a Louis Meintjes in course tactics (wait, wait, wait, wait, finish), just a ten times stronger version