What are the biggest downsides to "entrepreneur culture"?

People doing too much of their own thing and not working together as part of a larger plan to achieve big goals.

The potential for everyone going in their own direction and losing the common vision of the team.

I am unsure, I suppose that people seeing that they can do it on their own and no longer put up with the culture of hate at work, be their own boss, not have to put up with threats & attacks, or put up with daily racism, bigotry & hate speech. So it's harder to keep workers because they have other choices.

Sometimes there are longer hours to work and pay that decreases.

If that phrase is being used to excuse unprofessional behavior.

In a very dynamic environment, there will likely be disagreement over some direction and you could end up losing your brightest, most passionate team members - if not them actually leaving, they could also lose motivation for ongoing work if their projects are shut down.

You’re working all hours of the day.

Fueled by success stories many people thinks that building a company is all about raising funds. A product or a service is just a way to get the money. Often to burn it without delivering anything of value long-term.