Am I crazy for thinking my pup needs to go out every 3-4 hours?

My brother is a K9 dog trainer. I told him that I take my 16 week old pup out to relieve himself every 3-4 hours and that seems to be the sweet spot. Anything longer than that he will start sniffing and use it inside my house. He told me that I’m doing it all wrong, and that they can definitely hold themselves longer than that. That I “need to train them to hold it longer”. It’s not an issue at night. He goes in around 9:30 and he’ll wake up to potty at 5:30 am and then go back to sleep. I told him that just because he could hold it doesn’t mean he should hold it, and I feel like every 3-4 hours isn’t really unreasonable for a 16 week old… But he just kept telling me that he’s a dog trainer and to trust him.. thoughts? this way has been working for us and he rarely has accidents inside UNLESS I accidentally go over that 3-4 hr mark.