I try to change the formality (what is customary) and everything about it
[, but] people [are] killing people for a reason [, since forever].
[Just think about yourself, ] you make mistakes [and then] you don't regret [them]. So [you can] make a conclusion, [why trying to change the formality would fail].
I think it's about unchangeable human nature. People will always resort to violence because of reasons they deem important.
My interpretation:
I try to change the formality (what is customary) and everything about it [, but] people [are] killing people for a reason [, since forever]. [Just think about yourself, ] you make mistakes [and then] you don't regret [them]. So [you can] make a conclusion, [why trying to change the formality would fail].
I think it's about unchangeable human nature. People will always resort to violence because of reasons they deem important.
[Edit: typo]