You know I really don't know about that. Generally speaking people had more dispensable income after WW2 in the west than right now. People had a job lined up if they wanted to work, work was abundant. Back then any kind of job would pay well and most households had one earner. Being able to earn money through the internet today doesn't really replicate what these people had back then.

If you wanted to start a band you had multiple ways to promote them: I would argue some of the best known bands came from the pre-internet era (Beatles, Rolling Stones etc). In fact social media made it so you need a prohibitively high marketing budget to cut through the noise.