I’m not trying to justify it, but having to pay higher taxes for a joint income that puts you into a higher bracket after marriage is certainly not an incentive to get married.
Getting paid to stay poor and single isn’t an incentive either and that’s the end of the social spectrum where most of the destruction occurs.
Otherwise, it’s a marginal difference for most income brackets.
To get men with jobs interested in getting married again the IRS should allow husbands to depreciate their wife's beauty over 20 years. Many young women get the false idea their increasing beauty will last a lifetime. Then they overplay their hand.