Unfortunately, in this scenario, since a freelancer does not receive paid vacation time, they suffer 100% of the opportunity costs of missing out on billable hours as well as lost funding for things like retirement, paying for healthcare or the rising costs of housing. These are all exceedingly high costs that they must burden just to take time off. The situation gets even worse when there are large gaps between contracts. If a freelancer is young, he/she can absorb this for a while, but eventually it will become unsustainable and then they are right back to where they started from of working 40/50/60+ hours a week without vacations.
From my point of view, being a consultant/freelancer/contractor, whatever you want to call it, isn't a solution to the "Overkill Cult". If anything, it exacerbates the problem in the long run. What we need (in the US) are cultural shifts and at minimum basic policy changes such as mandatory maternity/paternity leave and increased annual leave that matches other western countries.