> giving your product away for free is just as bad a business strategy as it sounds.
Has anyone, anywhere, argued the opposite? Because this seems like beating a strawman.
> Copyleft licenses such as AGPL force adopters to publish changes back to the source repo or offer them via network protocols.
The AGPL specifically does this, other copyleft licenses (like the GPL do not for “adopters”, only for people redistributing executables)
> This is meant to deter third parties from offering competing hosted services
No, copyleft in general is about prohibiting downstream proprietary distributions (and also, in the AGPL case, proprietary hosted versions) it is not supposed to prevent competing software/services.
> Instead, why not do what traditional businesses are doing, sell a product, and simply charge for the value it provides?
That's what “open source” companies do. The thing they sell is the product (whether it's support and consultancy, the value-add of the enterprise version of an open-core product, or hosted SaaS.)
The problem with “prop-tech” is often, as this piece itself points out, but entirely fails to address in recommending “prop-tech”: “the world of FOSS is full of strong and established offerings with a zero-dollar price tag.” And making your tech proprietary doesn't stop you from having to compete with the open-source competition.