Why do you think it's just a couple "Democrats" changing sides or caving when Republicans need them to?
They are playing good cop/bad cop but they are both cops.
Sure maybe 49% of Democrats might have the best intentions but along as Republicans stand strong with their 51% they control basically everything.
It's naive to think that the rich controls everything except for the Democratic party. They do a lot of work to make it look like they don't own the good cop.