I will never use Xfinity/Comcast again in my life if I have a choice and will try to make sure everyone knows how shitty they are. Unfortunately they have monopolies in many areas and can be as shitty as they want, but if you have a choice I recommend never using them.
I can't believe that in 2021 these tactics are still legal. It's also stupidly shortsighted because in the long term I'm pretty sure they lose money by making everyone hate them. If it was easy to cancel, I would happily sign up again in the future without giving it much thought and would think positively of the company.
Edit: I also want to add that I was paying extra to not have a contract so I could easily cancel.