Since it is traditionally /women/ who change their names when married, this blind spot does not surprise me.
Or you go up on stage and say "I'm not just 'Gordon' any more. Call me 'Sting'." And everybody rolls with it, because no one cares about a bass player named Gordon, but a guy named Sting has to be cool. And then he actually has two completely separate names, that both refer to the same person.
In modern times, governments make you fill out a form and pay a fee, because now people need to know people that don't all live inside an hour-long trip radius by horse. And publishing a name change to hundreds of millions of people that may want to know about it cannot be done by soapbox and megaphone.
And those forms cause all kinds of problems. All the information on it has to fit inside the boxes, you see.
The business case for supporting such changes can be pretty weak relative to other features.
Women are half population and while marriages go down, they are not rare at all.
In recent decades, about 80 percent of brides choose to change their names after the wedding, both professionally and legally. [1] Most people marry at least once. [2] Women are half the population.
That being said, I do agree that in many systems, supporting name changes is not an immediate priority.
[1] http://www.nytimes.com/2015/06/28/upshot/maiden-names-on-the... [2] https://flowingdata.com/2017/11/01/who-is-married-by-now/