For me, free is always the best price. Conversely, you get what you pay for. Dichotomous witticisms aside, the core of this discussions can be deconstructed to time or money with a smidgen of “caveat emptor” thrown in for good measure.
If you have the time, go for free. It’s more work, more weeding through the BS, and struggling on your own to learn while keeping a day job. For me, though, this added effort provides an unintended benefit that employers love — tenacity and perseverance. Document your struggle so that you can describe how you’ll apply the same tenacity when solving their problems. It’s all win.
In theory, the paid programs have done all the distillation for you. That work has value. That’s why they can charge for it. It’s up to you to decide if the real cost matches the alleged value.
I’m not biased against paid training. I’m still paying off my college loans. But what I take from the author’s meaning is to be mindful. Don’t throw good money toward slick advertising, talking a good game, or celebrity endorsements.
There are at least a dozen metaphors that spring to mind. I’ll spare you and conclude with this: Time = Money. Acquiring knowledge requires an investment of both.