Spider-man was 15 when he started out. Tobey Maguire was 27 and Andrew Garfield was 28 during their run as Spider-man. Tom Holland is 20 but way more believable to be a teen in high-school than the other two.
In both the Rami and Webb films, Spider-man was at least 17 years old. And honestly, Tobey Maguire and Andrew Garfield's ages never bothered me. I was still impressed by their performances and apparently, a lot of other moviegoers were also impressed. I've seen Tom Holland as Peter Parker. Yes, he did a good job. But, being younger than Maguire and Garfield does not automatically mean I'm going to regard his performance as the best of the bunch. He simply has his own style, as far as I'm concerned . . . like Maguire and Garfield.