My father was one of EDITED siblings and his parents literally did not have food to eat, my father grew up with a level of poverty that his sister once told me “you cannot understand”.
His father was the youngest of a family that had a number of children that was closer to twenty then 10 and that was in Europe.
Unfortunately the mindset that you espouse is one that is a product of “Kochi Voitzem Yudi”.
The facts are that there is an inyan of “Berev al tainach yudecha” one must always endeavor to have children and more children.
As for mosdos going bankrupt.
The Gemaro tells us that schar talmud Torah is not part of the cheshbon, its on Hashem. (Mesechta Beitzah)
Either we trust Chazal or we do not.
Furthermore I personally spoke at length with a prominent Rov who discused these issues on a practical level with Rav Moshe zt’l and Rav Yackov zt”l. He told me very clearly that he had never ever heard of a heter for not having children becuase of financial issues.
He told me he guesses he is “old school” but the generations after the War understood that we have to do ours and Hashem will do his. He related to me that a prominent RY (who escaped the full brunt of the war in Shanghai) who was extremley poor and yet had a number of children in succession reacted to the questions of certain more modern people by exclaimg in shiur once “We live in a crazy world, each child is a world unto itself”. (This Rov had been in the shiur at the time)
The position that you are espousing is hopefully unpopular as it is in direct opposition to the “Ruach HaTorah”