That is what is happening though. It's an accurate description. These are cases of making content for corporations to sell ads against.

It is what's happening in some cases, not all. Also, language shapes thought, so we encourage this to happen if we frame it as "content creation". It's something to push against.

Note it's not even relevant whether something is commercial. Art can be commercial and not be just "content". A musician is not a "content creator" which happens to create content in the shape of music. "Content" implies it doesn't really matters, what matters is engagement and the platform (and advertisers, etc). It's not healthy to think of hobbies, art, and entertainment as exclusively about this. Imagine if Oscar Wilde, Herman Melville, Alan Moore, etc had been thought of merely as "content creators".

This is not a new idea. Stallman was already pushing back against this "content" term decades ago.