What argument are you making here? Government won’t do it because raising any taxes is bad?
Unpopular in practice is different from unpopular in concept (look at cutting emissions, for another great example), and both are different than bad. Other than that, pretty much: The government won't raise taxes because it's unpopular when they do. (Thank you for asking, by the way, It's hard to just insert "this is my thesis")
Sure, they might be forced to raise taxes eventually. Probably, even; it's happened before. Or, maybe some socialist firebrand will come in and make extremely progressive taxes their signature policy (meaning they have to go with the flow elsewhere). But, this is descriptively, factually, why hikes don't happen that much.
Now, normatively, you can make whatever you want of that.