It failed. Miserably. It substituted what it thought were "traditions of men" for actual "traditions of men".
I can't control how you feel.
While I agree with you that most Protestant churches stopped growing, they haven’t failed. They are still places a person can go on their Christian journey as they come to understand what the Bible says. They are still useful for that.
You’re welcome to believe where the RC church is heading and what it is now sanctifying can be aligned with the Bible. Every liberal movement today is being supported by the RC church. The RC church is not coming back to what it used to be. It is now fully one of the world powers of the Last Days.
Give some examples, please.