I'd have to say that a good percentage of the systems that include subs that I've heard don't impress me. The bass is overblown and unnatural and doesn't much resemble the live acoustic music I enjoy.
That's not to say a sub that has been well matched to the system and properly adjusted can't help with large orchestral pieces, but my exposure indicates "doing it right" is hardly a slam dunk.
Keep in mind that the majority of instruments don't have fundamentals that are all that low. Low E on a bass guitar is 41 Hz. Low notes on a grand piano are ostensibly lower, but they have a very heavy component of overtones that are actually louder than the fundamentals in that range. Large drums can also benefit.
However, the vast majority of music is in the midrange. I lose interest if the system doesn't have that right or if the added subwoofer screws up that balance.
In short, for some of us a subwoofer done poorly is a far worse offense than a system with a slightly shy bottom end