Sammy’s observations, such as "two crescents of white" (paragraph 1), suggest his extensive experience as a "girl watcher." He has also watched older women, as is indicated by his disparaging comments about some of the less attractive physical characteristics of aging. His remarks reflect his taste for youth and beauty, but also his own limited understanding of life as a boy of nineteen. His estimation of female intelligence in paragraph 2 about a "buzz like a bee in a glass jar" and his expressed lack of certainty about how girls’ minds work indicate, under the guise of minimizing women, a lack of experience with women on an adult level. His gesture to quit his job is at odds with his patronizing estimate of women, for it shows more respect than he overtly expresses.
Yes. The reason why Sammy's observations reveal his youth is because he only see's the women for their bodies. He does not care to get to know them. He thinks "If I quit then I will get some," so to say. His brain is not yet developed that he doesn't understand that, that is how life works. He is willing to throw away a decent job all for women he hasn't even known only due to the fact that they are appealing in their swimsuits.