A lot of the uses in Western countries weren't even to disperse anyone, they were used as giant speakers to broadcast messages, e.g. during Covid in Germany.
It's crazy to compare that to what seems to have happened in Serbia. It's like saying "Carter has used a hammer, too" when commenting on a murder, and leaving out that Carter used the hammer to build houses with Habitat for Humanity.
People make grand statements all the time and appeal to values they claim are universal. Then when you hold them accountable for the fact that they value they are claiming is not the same as the values they have supported, you get the "whataboutism" canard thrown at you.
If you support "Freedom of Speech" and support prosecution for speech, then you do not support freedom of speech. Even in a steel-manned case, you support freedom of speech "a" and I might support freedom of speech "b"; by pointing out inconsistencies, we are helping each other understand the real argument being made, not just the thought terminating cliche.
Just because one finds it tiring to have people expose their sophistic arguments doesn't mean that the rest of us don't see value in it.
Sure it is. The fallacy here is focusing on the messenger: THEY do this, THEY do that, if YOU do this, if YOU do that... But the messenger is not the topic.
Instead, focus on the initial charges and whether they are factually correct. The messenger doesn't matter. They could be a total hypocrite, they could have 0 values, they could eat babies, and still be 100% right on the issue. Not to mention, other messengers say the same thing, and attacking them won't make the claims incorrect, either. This is why the phrase "don't shoot the messenger" exists.
When you use whataboutism, you behave at least as poorly as the person you claim has no values, or who you claim is a hypocrite. This is because you yourself refuse to criticize the behavior present in the initial charges. How does sinking to what you believe to be their level, help resolve the initial charges?
tl;dr: there's a reason why 'no u' is considered a joke and not a serious defense of one's behavior
Neither precedent nor whataboutism are a good way to run a multipolar world. Both include literally all of the worst of humanity throughout history.
Even though we haven't evolved much since then, we don't have to be savages: Consensus of the majority of nations is a more appropriate (albeit not perfect) way to resolve multipolar issues.
The difference between a peaceful protest and a riot is usually just a matter of who's doing the reporting. Or whether the police have bothered to plant a provocateur in the crowd to throw the molotov that justifies the police violence.