Which is better, a toothbrush with small bristles or one with large bristles?

I heard that toothbrushes with small bristles clean every nook and cranny well.

I mainly use small ones.

I was browsing the shopping site and saw a toothbrush with huge bristles, so it’s fascinating lol

I wondered if the inside would be cleaned well if it was this big.

Isn't it really big? ^^;;;