Well, it's clear that this retort conveniently misses the point of Nikhil's original essay entirely. Of course, marriage can provide legal and financial benefits, regardless of whether children are part of the picture. It's also true that many couples without children still find fulfillment and purpose in their marriage. But Nikhil never said that marriage wasn't an important milestone or that it couldn't be rewarding without children. His point was simply that if you're not going to have kids, there is no reason to get married!
In short, the main purpose of marriage is to establish a family—not necessarily to fulfill any other "individual needs and desires of the couple." Whether or not those individual needs and desires come into play is beside the point. The traditional idea of marriage is more focused around procreation, rather than commitment and love, and it should be acknowledged as such.
The fact remains: if you are not planning to have children, then there really is 'zero' reason to get married in the traditional sense. Of course, if you find comfort and security in committing yourself to another person and receiving any potential legal and financial benefits, then by all means have at it! But just remember: there's no need to tie the knot if you're not ready to start a family. After all, with great freedom comes great responsibility!