It’s impossible to please everyone. There’s no real reason to try and please everyone, because for every one person you please you are by default going to upset someone else.
Besides that, there are going to be plenty of people you don’t like. Why make an effort to please them? No real reason to do that either.
But to deliberately make an effort to upset someone is not a smart move. Make no mistake: when you talk shit in confidence, with people you trust or in quiet backrooms, you are still making an effort to upset someone. Anything expressed has the potential of being repeated and repeated and repeated, and that’s a risk you should acknowledge before you express anything.
Sometimes competitors (think: athletes) talk shit because they know the implications are limited to a game or situation. Maybe it’s in jest (though, now it’s usually spun by the news headlines too). Sometimes talking shit is an excellent motivator for the other party that pushes that person to new levels. That’s all well and good.
But if you’re not talking in [obvious] jest, or have no intention of trying to raise the level of play of someone else, there is no upside to talking shit.
You’re left with is a lot of downside risk with almost nothing to gain. Is it worth it?
That’s ultimately your call to make, but the expression, “If you don’t have anything nice to say, don’t say anything at all” has a lot of wisdom regardless of age.