In Canada and UK this violence comes from Sikhs and Pakistanis.

Due to this, in the UK specifically, racism towards Pakistanis has a level of taboo attached to it.

And in Canada perhaps there is a taboo towards being racist towards sikhs. (Although I don't live in Canada, I have family there and apparantly the Sikhs there can be quite violent)

It's unfortunate though that Sikhs in the west are too far stuck in the khalistan rabbit hole, that they won't stand up for racism towards indians ever.

If there is ever violence from a Sikh in Canada due to racism, it'd be due to racism on the basis of being a Sikh, not an Indian. They view themselves as "khalistanis" unfortunately. Indian folk whom identify themselves as Indian, with the intent of ending racism to ALL Indian people, need to start becoming violent and start protesting.