Does my dog look skinny?

He’s a purebred golden retriever. He’s only 6 months old but is about 40 lbs and long legged. I always thought he was huge, especially for his age but I have a couple family members who think he’s skinny. Vet has never seemed concerned but he has a couple months before they have him in again. He’s had dewormer and all that as well. Eats like a horse!!

Here you can see he’s a bit long legged:

Here he is from the back (so cute 😭)

And here he is in comparison to me at 5’4”.

He almost looks fat to me 🤷🏼‍♀️😂