Is it normal to be banned from a big community because of a comment critical of a "left leaning" dictatorship? (Cuba)

In .ml, yes. Your post and comment can be very easily removed for arbitrary reason but usually anti-communism, regardless if it's factual or not. For example, your comment is removed because you criticise communist country and they don't like hearing that.

ml's folks, especially the mod and admin, have a very thin face, just like communism leader, and will only accept anything good said about communism. My comment got removed for misinformation because i said china trying to claim my country's sea as theirs.

There's also the micro-aggression going on with .ml, they could talk shit about anyone but if you use the exact point at them, your comment gonna get removed.

It's very similar to what china is going through right now. In general, just don't interact with them.

In .ml, the clowns that moderate that shitshow will remove/ban you for simply being a “lib” or “blue MAGA.” And yes. These were actual reasons for removal/ban in the mod logs.

If you ok, there’s mods that remove under rule 1, yet you can see plainly that the comment removed does not break a single rule.

I’d advise to block that shithole and forget it exists.

People who downvote please try to articulate why, I'm baffled.

It depends on the community, instance and your post.

My advice is to simply not care that much about bans and move on.

Unfortunately since your post was removed we can't see what you actually wrote, and since you didn't post which instance the community is part of, we can't use that to give you more information.

There managed to retrieve the post:

It was prophetic to talk about blackouts before the one going on now.

Just lurk in the .ml instance for a while to get a feel for what they cheer and dislike.

All instances have their own flavors and that’s one of the cool things about Lemmy.

Personally I like to criticize China, Russia, North Korea and Cuba along with everything else so I get a detention there occasionally.

Yes, it's normal. Lemmy is a left-wing echo chamber and anything that's not aligned with the point of view of a given community (even if it's supported by scientific proof, valid concern or reasonable doubt) you will be downvoted, ridiculed and/or banned. Just ignore close-minded mods and users and be yourself.

Rule 5. Locking.

The fediverse is formed by a lot of servers that contain each communities. Each server still has some room for their own ways of doing things, so there can be nuances to be paying attention to.