Oh, I guess if you define the shidduch crisis (nonsensically) as too many girls who want to marry kollel boys, you could say that kollel causes it.
Why any different than those who claim that boys go OTD at a much higher rate than girls?
Besides, it’s not that they want to marry them, it’s that they put their self-worth into being married to them, and therefore need to be married ASAP. If they were willing to wait 5 years we wouldn’t have the same crisis.