The better question is: how many of us would allow our sons to marry Rus? Her ancestry is a shainda. Her great great grandmother slept with her father. Would we allow a shidduch like that?
Imagine the case: A Shadchin calls up you up and says she has the most wonderful girl. A balas chesid, machiv torah….all A+++++. But, she is a product of an incestuous relationship. Would ANYONE today allow their son to date her? I do not think the greatest rosh yeshiva today would allow his son, the future gadol, to marry her.
What Boaz did was AMAZING, but I do not think anyone can compare themselves to him.