A lab-grown brain organ grown in a petri dish is not a fetus brain. It's the size of one, but it is not.

Labeling that tissue as a fetus brain can encourage many people (I hesitate to say which groups, though you can guess) to start their warbling even if they're wrong.

Making a point of saying "lab-grown brain organ," or organoid (though it sounds kinda like 50-ish pulp sci-fi), helps keep them docile.

Not splitting hairs or arguing for fun. When posting science articles, accurate descriptions are important.