I will be responding to each point in this poor excuse of an argument by numerical order. I've already read both the subheadings and ellaboration for each point, but will be copy-pasting (just) the subheading since it's more convenient. Just to make this clear, I only speak in run on sentances, so be warned.
1) Despite the modern PC sheen of “inclusivity” and “equality,” marriage is still that same old patriarchal institution
Yes, the original idea of marriage was to strap woman to man so that the child/ren they had were the father's (no wonder adultery and havind children out of wedlock were so heavily frowned upon). Yet as we all know, that idea of marriage is severely outdated (not to mention toxic) and is no longer apart of the "modern" concept of marriage. I cannot doubt that plenty of people still practice that idea of marriage, but I don't think that's a good enough reason for people to just not get married because there's other awful people out there.
2) Marriage benefits men and not women
I read the first item linked and almost wheezed out my spaghetti. It's a moderately short page, I'll admit. I was hoping it would make up for it with some actual informative research, but apparently not. I did find "women experience greater physiological and psychological reactivity to marital discord because they typically occupy subordinate (lower status and less powerful) positions relative to their husbands" (for full context, please click on the link to the site) rather intresting, to say the least. I don't know how they got this information or who actually conducted this study, the methods used, ect. Basically, this entire page is useless. If you can't state your sources, don't even both quoting them. I'd also like to point out that, even without marriage, a woman can still be in a less "powerful" position than their male partner.
3) Being a wife sucks
I must admit, a point was indeed made here. I can see this kind of mentality being glorified in the early to mid 1900s and probably by my homophobic cousin, too. Sadly enough for SUSAN COX, this isn't some 90s sitcom. The bumbling oaf trait is mostly performed in comedic television, such as The Simpsons (E.G Home Simpson, in particular). However, comedies, such as The Simpons, are just that; comedies. Comedies produced to entertain. A bumbling oaf can certainly create some more hilarious scenarios than a serious lawyer (then again, it would depend the audeince's taste in humour). If you prefer the latter, there is a wide selection of comedies featuring multiple head-strong characters (Mrs Brown, bless my poor soul you abosulte Godess).
Your whole point on women's employment options/payment doesn't seem to correlate to why somebody shouldn't marry (or you havn't pointed out the link between these two topics), so that's all I have to say on the matter. The whole beauty standard thing doesn't seem to have anything to do with marriage, besides the whole "a pretty/handsome face could land you a secure, stable marriage!" thing. SUSAN COX said that women are expected to change themself for the male desire, and although I do not agree with that, I'm going to pretend I do for a second. A woman being expected by external groups to do herself up for her future husband doesn't affect her quality of marriage, unless she were to marry an utter douche. In that case, it's not marriage that's at vault, but rather the husband. "Don't marry because maybe your husband is bad person" seems to be the moral of the story
4) If you’re getting married thinking you’ll never be lonely again, buckle up, because marriage is totally isolating!
I'm going to be honest here, SUSAN COX, this point was quite articulate. Here, take my internet points. I have no reason to doubt that marriage is isolating, and not wanting marriage to take a toll on your social life is totally reasonable. Marriage is more binding (on both parties), due to how difficult actually filing for a divorce can actually be (and other contributing factors).
5) The sex stops being good
Ah, SUSAN COX, more internet points for you. Men usually do have a higher sex drive then women (not always the case!), so it makes sense how it could be both emotionally and physically draining for the party with a lower "drive". Overall, good point
6) and 7) relates to my mention on divorce in 4)
8) Getting married doesn’t make you an adult.
I found this one (to my happy surprise) funny and not because I didn't like what they had to say. Yet, it was ruines by the sudden jab at the "patriarchy". It depends on the type of relationship you have with your husband that will decide whether or not he's a "man-owner". If you marry an abusive spouse, it's not your fault, but you can't blame marriage itself for shitty people.
9) Weddings are overrated
Fair enough, really. Weddings usually do put people off from marriage.