If other governments have a problem with that they can get fucked.
What's more likely are additional restrictions on international trade and immigration. The great experiment with globalism appears to be winding down and powerful countries are decoupling their economies from each other.
But ultimately this is effort to moderate west, well smaller countries like Canada (increasingly dependent on Indian immigration) to control what domestic diasphora voices they amplify. Which may very well backfire. Or not - decades of increased PRC immigration + students in Canada was associated with fed gov playing down PRC dissident voices (and still do to some extent). Short of getting rid of problems via extradition - which is political suicide for Canada and won't happen - India limited to raising political cost of associating unfriendly diasphora politics. Canada isn't going to hit immigration targets without playing nice with either India or PRC. So there's no reason not to push, and almost extra reason to. There's likely going to be millions of new Indians in Canada by 2030, India doesn't want dissident elements to organize, and is incentivized to make domestic politics difficult in Canada if they're allowed to.
The asymmetry you imply does not exist.
There wouldn’t be an issue if New Delhi had stuck to wanting to whack a Canadian.
Sure. There isn’t the necessity of a military response here. But it was exceedingly dumb. New Delhi has a rogue security element. I, at the very least, didn’t see that coming. From the indignant response, it appears Delhi didn’t either. That’s concerning.
[citation needed]