The ritual is often more important than the belief system since it entails membership in a community. The belief system is often taken with a grain of salt.
This is why religious denominations are not in lockstep.

The problem with this view is that the religious system itself might be harmful and support for it questionable. I think this is a true atheist position.

I can see situations in which the religious system can be dealt with politely if it doesn't become proselytizing and tribal. But I choose personally not to support a religious system as credible although I can remain polite about it when dealing with believers. Most of the time, I choose to ignore any conversations about it because I don't think it merits that.