The general expectation is that blue collar jobs pay more at the beginning, and white collar jobs pay more at the end. So at 20, the white-collar college student is eating ramen and wearing thrift store clothes and the blue collar worker is already making a decent salary, driving a new car, thinking about buying a home. At 40, the white collar worker is doing well, has a house and a car and a family, and the blue collar worker is about the same. At 55, the white collar worker is in the prime of their career living comfortably, making very good money, and achieving a level of prestige while the blue collar worker is living about the same life they had at 40, but with more physical ailments slowing their working ability.
This is what has traditionally been believed and does not necessarily represent reality, but it explains the tradeoffs each route offers.
Increasingly that expectation appears to be built on some very shaky assumptions regarding lifetime income.
This is anecdotal, but a blue-collar acquaintance who studied for a 3-year power plant safety program purchased a detached home a full 7-10 years before his peers who went to university for four-year degrees. There wasn't much parental assistance involved in the home purchase.
Being able to make enough to cover a mortgage and sock some money away in an investment account can give you a financial boost that compounds over time. If you live in an expensive housing area, that boost could end up exceeding what white-collar grads net out to, 15-20 years later.
This is what has traditionally been believed and does not necessarily represent reality, but it explains the tradeoffs each route offers.