Why are the better people now less willing to get married?

Not today, marriage sucks, 50% divorce rate, men get screwed in a divorce. I no long have a GF, hook ups work fine.

Marriage is an outdated and obsolete institution.  It NEVER lasts these days.  There is NO reason TO get married except if you are somewhat of a Sadist who loves to suffer or be abused.  People these days don't want to get married because they are SMART!  They neither want nor need the grief that comes with it.  I know I surely would NEVER get married again.  In THIS lifetime OR the next!  

no benefit for a man to marry

I see no evidence of that being true. Could you supply some sort of example or reasoning or observation to support your statement? 

if you do a cost - benefit analysis on the likelihood of the marriage lasting it's not very promising. the government has no business being involved in people's private lives like this. it's long overdue that the INSTITUTION of marriage was abolished. 

Because we are already married. 

How could anyone know if your claim has any validity?  Better?  In whose eyes and by what standard?  If you mean "more affluent" then they tend to be more single minded and selfish in the pursuit of wealth and not keen to share or cooperate with someone else.

What's the point of marriage? Why let the government into your bedroom?