This depends on who you ask. There are some who would say that marriage is honestly just a piece of paper, and there are others who say it’s not just a piece of paper. The former is the trend nowadays. About fifty percent of couples live together for years before they actually get married in the United States, with the other fifty percent getting married first.
However, marriage - regardless of your views on the marriage certificate and the relevance it has to the marriage - is what you make of it. If all you see when you think of marriage is a piece of paper, it’s not for you. If it means more to you, it’ll probably last longer and mean more.