It's also probably good for you. I believe the brain learns to do what you are used to do "better". If you spend a lot of time ranting, you'll probably rant more. You might eventually end up wired to rant against anything showing up.

A relative of mine is like this, they are annoying with this. It probably only makes them less happy and this person seems to be annoyed by anything [new]. There's no upside to this. I personally want to avoid being like this at all cost. It's so much more enjoyable to be around someone who finds joy in insignificant things instead. I probably won't be this person but becoming closer to this is probably nice.

You probably don't want to be someone who is positive at anything, even shitty stuff, but there's usually some margin.