The same question can be asked of your religion. In the past I have registered to post on Mormon sites and the control on the conversation was very strict. I have also been on “Christian” sites that were just as strict. On one site a member posted rhetoric they got from an anti-Mormon site. I responded with a correction of the false information they repeated and was duly labeled a Mormon and kicked off the site.
Knowing you and examining the formation of your question leads me to believe you are simply rattling the cages, so to speak, and not really looking for answers. However I actually posted a question similar to yours years ago. Why do some religious groups feel it necessary to attack the beliefs of other groups? I think this is a fairer question than your broad statement.
I believe it is because they feel their ability to interpret scriptures is superior to other people’s skills. This makes them feel that their beliefs are obtained from a higher intellect than ‘those other people’. I believe, and this is my observation and not intended to be a factual statement, that the vast majority of people claiming to be Christian are not and their faith is indeed weak.
(Mat 22:14) For many are called, but few are chosen.
I believe it is this group of people, from all manner of faiths, that fear other beliefs and feel a need to attack them.
You claim to be a Christian so you should be able to answer that question yourself. Is your faith so weak that you come to this forum to attack the beliefs of others and thereby feeling justified in your beliefs? I’m just asking.