I don't think that typical jobs from 50 years ago were better in any of these regards. On the contrary, the well-paid blue collar manufacturing jobs that are associated with bygone better times in folk memory were quite bad by these measures. Just imagine working on an assembly line.

Focusing specifically on North America, where these trends appear to be the most pronounced, the key issue, in my opinion, is the distribution of status. Fifty years ago, it was possible for a person of average or even below-average abilities to have a job, lifestyle, and social status that was seen as nothing spectacular, but also respectable and nothing to scoff at. Nowadays, however, the class system has become far harsher and the distribution of status much more skewed. The better-off classes view those beneath them with frightful scorn and contempt, and the underclass has been dehumanized to a degree barely precedented in human history. Of course, these are not hereditary castes, and meritocracy and upward mobility are still very strong, but the point is that the great masses of people who are left behind in the status race are no longer looking towards a mundane but respectable existence, but towards the low status of despised losers.

Why and how the situation has developed in this direction is a complex question that touches on all sorts of ideologically charged issues. Also, some would perhaps disagree whether the trends really are as severe as I present them. But the general trend of the status distribution becoming more skewed seems to me pretty evident.