The whole concept of large families in the past was borne out lack of birth control, high infant mortality, low longevity amongst other factors.
My roots, both my mom and dad came from families of 7 and 9 respectively and I am from a family of 3 and I only have 2 children.
Seeing that we no longer till the fields, there is no need for big families. Once can effectively provide for replacement size families as the skill sets they require to survive in the modern world do not include farming.
But as we are now devolving where the previous idea of that all prepared to work would be guaranteed a job has gone by the wayside. Where I live, it is not uncommon to see the extended family coming back, kids caring for parents or parents having to accommodate thieir kids and grand kids.
I used to be the breadwinner in my household and made a huge salary, now whoever can find a job, however meager contributes to the household so that there is at least food on the table. We learned to adapt and thankfully I own everything and owe no one a cent. This makes it easier. We only have to cover utility bills.
So as for reducing your lifestyle, it is possible but not pleasant.
Now had I had 4 kids like I initially wanted, then my situation would have been far worse. We decided after 2 that was enough.
Communities of yore have gone, when I was rich, we helped the needy out with food hampers, bought them necessities like bed for their kids, gave money to some for surgeries and now that I am in the need department, there is no one to assist us. Not complaining but that is how the cookie crumbles. I essentially did everything right to provide a better life for my family than my dad was able to, got 3 degrees and all that good stuff but that means squat when the economic mechanisms fail and if you are over 50. Fortunately I am multi-skilled and when I do get a contract, it is like christmas, we get to eat steak
my services are high earning but the clientele sadly is small.