The problem with Existentialism is that it can lead to despair. That unpleasant effect comes about because the individual is required by the inherent meaningless of the Universe, in Existential philosophy, to generate their own personal reason for existence. The creation of personal meaning takes effort, and an individual must be enthusiastic and have considerable reserve energy to be able to delve into Universal truths. When a person falls to the energy level of average human beings they don’t have the enthusiasm, or the mental reserve to cope with that scale of problem, and therefore to explore the existential life view often brings failure, despair, exhaustion and a choice of suicide or accepting the answers provided by an over-abundance of self-proclaimed authorities. The vast majority choose to follow the crowd and participate in whatever answers to universal problems their family and friends accept. It works and people become members of their society’s various subgroups. They then take on the symbols of their self-chosen group and proceed with their artificially narrowed lives, and the existential questions never come up again, because their accepted authorities provide pat answers.
I have published various statements acknowledging this problem, such as — Your time and attention are your most precious possessions. Use your time well! Without time you can do nothing, and without your attention everything is meaningless. — Participate in your world. Make the best use of what is in your power, and be contented with the rest as it happens. — It is wisdom to know that idleness brings boredom and despair; a happy life is filled with kindness, humor and accomplishment. — Unless we observe others, and do something to help them toward their goals, we miss the greatest source of happiness.
Existential reality is too demanding for most humans so they choose to become willing slaves to an ideology.