The adverts on TV are a clear indicator that bullshit jobs exist, they are simply not necessary.
Further, much of modern society is not necessary. Fast food is stuff you could make at home, but you're too busy at your advertising job. And so bullshit jobs beget more bullshit jobs.
What's happening in western countries is that trade deficits - the slow bleeding of wealth - are happening while much of the upper middle class engages in bullshit jobs and the lower classes engage in burger flipping to each other and the upper middle class.
Not much productive activity is actually going, less than 20% of the population is engaged in manufacturing, resource extraction, counstruction, and farming, and the rest is bleeding out the accumulated wealth from the past (mainly by countries like China wanting to buy our pieces of paper - dollars - and giving us our plastic and electronic toys).
The real problem is the free market economy is short sighted. Private investors can only think short term because they simply refuse to risk money on very large but high payoff ventures.
The government needs to step in and spend, spend, spend on large ventures like space travel, medical science, robotics for bullshit job insanity to end.