Except that other denominations don't claim, *Once a baptized ______, always a baptized ______* like the Catholic church does.
It's not pointless to formally and officially distance yourself from a person of Hitler's character. It shows that the people doing so, or church in that case, are aware of what is going on and formally and officially denounce what is going on and accept no responsibility for it.
It changes nothing as far as the broken relationship in a practical matter, but it does make a statement and that would prevent the types of accusations that the RCC is now facing concerning Hitler.
It's really no different that people complaining that muslims aren't denouncing jihadists, therefore they aren't really condemning them. If someone says they're a moderate muslim who doesn't support terrorism or acts like 9/11, they'd better outspokenly condemn it or nobody is going to believe it.
Lack of outspoken condemnation can be rightfully interpreted as commendation and support.
Lack of outspoken condemnation can be rightfully interpreted as commendation and support.