Is what the questioner’s friend does — expressing admiration for church bells and quoting saints — wrong, and is the questioner’s reaction considered extremism?

It is not for a Muslim to rejoice at the sound of church bells; rather, he should detest them for the sake of Allah, because they are a symbol of their false religion, which is based on disbelief and polytheism. The Prophet (peace be upon him) disliked them because they are a matter pertaining to the Christians. Allah has compensated the Muslims for them with the Adhan (call to prayer), through which the gates of heaven are opened, devils flee, and mercy descends.