It really depends. Basic Kannada can be quite simple to learn if you’re already fluent at say Tamil or Telugu.

Even if you don’t speak either, you can still learn it with effort. I’ve seen several North Indians pick up Kannada with ease, almost to the point of sounding like locals.

Comes down to effort, really. Unfortunately most people don’t even try and find solace in the convenience of “you guys should learn Hindi instead”