If it's what your priorities are you can have a home, cars, max out your 401k and be paying back student loans on a single entry level tech salary.
This requires that you put up with a long commute, beater cars, an old house and DIYing a good chunk of skilled trade work that you could hire someone for. You'll be bringing your own lunch to work, drinking beer from a can and not building much cash savings at that stage. Nevertheless it's sustainable on a single entry level tech income in a major urban area and living a couple hours away.
I think that increased spending on luxury things has by implication de-prioritized the "life milestone" things.
Generations ago people bought a house and started a family first. Now people accumulate wealth first and settle down later (which is probably a reflection on the fact that the lifestyle needed to accumulate wealth is not very compatible with settling down).
The reason for this may be that, in the absence of public social safety net, family (and particularly close family) serve as a safety net, and particularly children, once they are able to be productive, can be a kind of safety net against infirmity for their parents.
- lack of birth control and related education - desire for “free” manual labor to work stuff such as farm fields - desire to ensure continuity of one’s family tree (i.e. high mortality rates for infants and children due dangerous conditions and/or lack of healthcare)