Some people, freelancers as well as clients and those middlemen that are unfortunately very common in this market, seem to fundamentally misunderstand what a freelancer or contractor is.
Freelancing is not some alternative form of employment that allows you to conveniently dispense with social security costs.
A freelancer is a self-employed service provider. Like with any other kind of self-employment you’re responsible for your marketing, sales and for reasonably insuring yourself against calamities that might happen in life.
If you try to outsource those core responsibilities to another entity you only have yourself to blame. The same applies if you act irresponsibly in terms of finance, e.g. by spending all your income before costs and taxes are taken care of (if you have a problem with that Profit First is a great framework to help you).
That said it’s well-known that the software industry is overly dependent on mostly useless middlemen like Freelancer.com . So, perhaps it’s quite understandable if you turn to them when you start out.
You should always be aware however that they’re neither your insurance nor your employer. They don’t protect you. They just take a cut from your hard-earned money. They want you to commoditise yourself by solely defining yourself in terms of a bunch of TLAs because those ‘profiles’ are easier to sell.
The sooner you extricate yourself from that dependency the better. Putting all your eggs in one basket like the review suggests the author did is recklessly negligent.