Activists doxed 1,000 Belarusian thugs.

We don't know from the information in the article whether they are hackers. We also don't know whether they are crackers — we don't know whether they had to break computer security to get the data.

But I can say with certainty that they struck a good blow against Lukashenko's tyranny.

Doxing someone is like a kind of violence. Ordinarily, it is bad to do violence to others, but there are situations where it is justified. When the thugs are carrying out violent repression of dissidents, it is justified for dissidents to respond with counter-violence.

It may or may not be a good tactic. In this case, because doxing is a warning rather than actual physical harm, I think it is a good tactic.