As much as I abhor the state and wish we live like the state of Cheran (ironic of me to say state in this case, I know), anarchy will only work in a very small group, where everyone knows each other, are like-minded enough to not abuse each other's goodwill, and respect each other's personal boundaries.
This is heavily promoted by mainstream media and language
Anarchists are pacifist
Many people seem unable to comprehend how a community might defend itself without a standing military and so assume we must be unwilling to defend ourselves.
Nothing can be accomplished without coercion
Because most of us have grown up within strict hierarchies coerced to do things we don't want, we have trouble imagining any other way.
It kind of illustrates why anarchy is as doomed to fail as libertarianism; note the use of force and the fact that the anarchists friends are not there defending him.
Anarchy cannot defend itself from organized outside threats because it is, by its nature, not organized, particularly in its use of force to confront fascism.
What is the best example of something built by anarchists?
For the sake of curiosity I'd leave this quite broad. Buildings, institutions, inventions, art. What's the showcase example of what anarchy has created for us?
Let’s think of fun comparison for a second. Mods/admins are government, judges and police at the same time. This is equivalent of an authoritarian regime.
Now if the mods would be elected by users that would be a democracy. Then if there would be no mods - there we have - anarchism.
In authoritarian regime views of government dictate everything. In democracy people decide who will dictate a lot with various safe guards. In anarchy people directly decide what views are popular and what is a crime, sometimes by groupthink.
What it tells me is that among many anarchists groups some will be absolutely terrible place you wouldn’t want to be in for even a second and some will be amazing but it isn’t a rule but it depends on the people that make up the given group. Obviously if you are POC you would hardly want to be in a racist community, I mean they would probably kill you on sight with their views being very white centered to say the least. So you keep going to find your community assuming you luckily got away.
Then you meet community of religious gun freaks flat earthers that you may want to skip as well. Finally you find your dream group but it was raided by some barbarians