I gave a rant yesterday about this. But I have to say it again because it's so gratifying. It went like this

Me: "you should patch the module instead of using it for your python unit test."

Them: "You keep telling me this, but maybe there is a better way"

Me: "there is, I'm telling it to you"

Next day, Code review.
Me: "You need to change this"

... silent on the issue ...

On a call...
Me: "You need to patch the module. Don't mess up the namespace."

Them: "I don't think so, X did the work"

(In my head: then what did you do)

Me: "We can grab whoever you like Y, X. Let's see if X is busy"

... X isnt busy, hops on call 45 seconds later.

Me: "we're using the module, we should patch this'

X: Muses the thought for 2-3 seconds.

X: "yeah... Yeah we probably should patch that"

Moral of the story, don't take shit personally unless your right... Then relish in. But if your right and X says otherwise, you can always + a rant.