You apparently don’t know about poverty in Russia to claim that sufficient food wasn’t a real concern. We can’t uproot what Chazal and the Shulchan Aruch tell us based on speculation regarding when Gedolim ultimately found their shidduch. This is especially true in a situation where there were hardly any from girls to marry. Are you saying Chazal were wrong.
No. Your Rav is not chayiv misa because he’s a shogeg. You, at this point, are no longer a shogeg so if you delay or allow your children to delay, you would be chayiv misa, unlike your Rav and your friends who are, as I said shogegim.