To be fair to those millions, the politicians involved in trying to get brexit through were going everywhere spreading propaganda on how good it would be (eg: 200 MILLION MORE MONEY FOR NHS), so yeah I think they have a lot of the blame.
I know they lie all the time, but still.. it made the vote (in peoples heads) "Give £200 million to NHS?", so they picked yes to leave, but pretty sure the NHS didnt see that money, because it was either a lie from the start or they needed it to make up for the grave losses from everywhere else because of the change idk.