It is actually scary seeing people who just fully aren't aware that marriage is about way more than a paper or about "getting the government involved" with your relationship. Marriage provides a lot of legal and financial benefits that I don't think people are fully aware of, like:
having joint health insurance plans or being under your spouse's insurance
social security and life insurance payouts
more tax things than I can honestly think of
combined credit scores for the purpose of applying for a loan or mortgage
hospital visitation rights
the right to make medical decisions for your spouse when they're unable to; if there isn't an established medical directive AND a durable power of attorney of healthcare for your partner, these rights go to the next of kin even if they're abusive or you're estranged
the ability to sue on your behalf if you die
the right to make decisions regarding your last rites and your funeral
CHILD CUSTODY!!! if you have a child anf they are not biologically your non-married partner's or legally adopted by them, there is absolutely no guarantee that your partner would get custody if anything happened to you; even if it's in your will, wills are just suggestions in terms of child custody, and the court will hear out any adults who have a claim and will often side with biological family (your siblings, your parents, or the child's other bio family) over the parent's unmarried partner, even if you've been living together for years and the child knows them as another parent. this has been used by abusive and bigoted family to steal grieving children from their other parent
Do I think all of these things should be exclusive to marriage? No. Do I know another solution? Also no. Is this the realoty we live in regardless? Yes! There is a reason why marriage has been something people have fought for for so long and so hard, whether it's interracial marriage or gay marriage or whatever else, these are all rights exclsuive to married couples and something that you absolutely need to consider when starting a life with someone, especially if you have children or plan to have them in the future.