There is far too much intolerance, violence, misery and death in the world today caused by people acting on or motivated by their u̶n̶s̶u̶b̶s̶t̶a̶n̶t̶i̶a̶t̶e̶d̶ ̶r̶e̶l̶i̶g̶i̶o̶u̶s̶ beliefs.
e.g. USSR anti-religious campaign of 1928–1941:
"The campaign began in 1929, with the drafting of new legislation that severely prohibited religious activities and called for an education process on religion in order to further disseminate atheism and materialist philosophy. "
"The main target of the anti-religious campaign in the 1920s and 1930s was the Russian Orthodox Church and Islam, which had the largest number of faithful. Nearly all of its clergy, and many of its believers, were shot or sent to labour camps. Theological schools were closed, and church publications were prohibited.[1] More than 85,000 Orthodox priests were shot in 1937 alone.[2] Only a twelfth of the Russian Orthodox Church's priests were left functioning in their parishes by 1941.[3]"
"Stalin called for an "atheist five year plan" from 1932–1937, led by the LMG, in order to completely eliminate all religious expression in the USSR.[43] It was declared that the concept of God would disappear from the Soviet Union.[43]"
https://en.wikipedia.org/wiki/USSR_anti-religious_campaign_(...
I used your original wording with strikethrough to make my point, but I think this would be a more accurate statement:
There is far too much intolerance, violence, misery and death in the world today caused by violent people acting on or motivated by their beliefs without any restraint.
This applies to any kinds of beliefs be it religious, political, economic, philosophical, moral, etc.