No one has to own a 1911 any more than they have to own any other handgun. However, there a definite reasons that the design has endured and been in continuous military use since it's inception and after 100+ years is more popular in civilian circles than ever. For those reasons alone it's worth at least trying one out at the range.
For those that choose to carry 1911s over one of the many polymer offerings, the decision is driven by more than capacity and weight. I prefer the ergonomics, the trigger, and the 'shootability' of the design - they point naturally and have a fit/feel in the hand that has yet to be replicated in polymer - and the 1911 trigger is the one that all other pistols are measured by. Additionally, they're nearly infinitely customizable, so, if you choose to, you can have one made to fit your needs/specifications.
While I've owned/shot/carried/been issued pistols and revolvers of many different types from many different manufacturers, my preference after almost 45 years of shooting handguns is the 1911. I have no need or reason to switch to something else. However, as much as I like them, I won't push my choice on someone else, other than to say give one a try and see what you think.