As, b’derech klal, we don’t do polygamy these days, by virtue of the fact the men are married they are by definition removed from the dating pool.
Unless you’re living in a patriarchal society I don’t understand how multiple wives wouldn’t be a constant shalom bayis meltdown. Let’s say you live in modern day Israel. Now back in the day each wife would have her own tent she lived in but in our time would each wife need her own apartment? It’s impossible for a lot of families to afford even one! Would they all have to be next to each other in different neighborhoods or even cities?
Would all the families get together in one house for kiddush or would the husband have to go from dirah to dirah making kiddush for each? Or would he just do an entire seuda in once house and rotate? Imagine the jealousy and arguments that could arise from whose turn it is to have tatte for the kiddush or seuda? We are just one husband and wife and can’t go one seuda without the kids arguing over who gets to sit in which chair.
Imagine the arguments if the family spent more on the bar mitzvah/wedding/etc. of one wife’s kids than on the other wife’s. If the husband gets in an argument with one wife what is his incentive to try and make up with her when he has another wife he can just go spend time with and forget about the one he was fighting with.
These are just a few potential conflicts off the top of my head – if you really want to get into it I’m sure there are dozens more. B’kitzur it’s opening up a pandora’s box of problems. Even if polygamy could help the shidduch crisis (and who said it even could) I think it would make a much larger crisis of broken families, broken hearts and messed up kids.