Am I right that people best at writing are novelists rather than poets?

I would not want to read a legal brief or a scientific article written by a poet.  But I would not want to read a poem written by a barrister or a virologist.

Some novelists are fine poets. Some poets are good novelists, thought I think they sometimes get carried away by their descriptive urge.

I don't at all understand what you mean. Are you suggesting that good novelists are better writers than good poets? If so, I'm afraid you're talking nonsense.

No, you're not. And writers are not divided into 'novelists' and 'poets'. Quite a few are both.

Best at writing what? Poets tend to be good at writing poetry, novelists at writing novels, journalists at writing articles, scientists at writing scientific papers etc.

That would be true. Poets are good with sounds.