One interesting thing about comparing the relative merits of an entire adult life of monogamous commitment vs an entire adult life of non-monogamous free love is that no one person can try both.
That is a vacuous observation. It applies to any choice that one maintains for one's entire life.
The non-vacuous point is that different people live fully on opposite sides of the spectrum, so do whatever you want to do and find the balance that makes you happy.
Doesn't the fact that it applies to any such choice make it not vacuous but all the more profound?
Not by my standards. Not only does the aphorism apply to any choice, it also applies to any time period. It is simply the observation that you cannot do something and not do it at the same time. That doesn't seem particularly profound to me. But at the end of the day profundity is in the eye of the beholder so YMMV.