That is mostly valid if you're at least decent looking and have a personality that's conducive to getting laid (social, outgoing etc.). Otherwise, you could set yourself up for frustration and misery.
Not to derail the conversation or fixate on this element, but being in the right place, spending time outdoors/being active (others have touched on fitness), and having a low-stress lifestyle all make anyone more attractive and provide more opportunities. I was being a bit facetious; "get laid" is more of a placeholder for "create some social bonds and have fun."
That is mostly valid if you're at least decent looking and have a personality that's conducive to getting laid (social, outgoing etc.). Otherwise, you could set yourself up for frustration and misery.