But it's frankly not true, despite your desire to appear sardonic

For instance, does Richard Stallman fit this mold?

RMS' vision depended on as much adoption of Free Software as possible to both starve proprietary software producers and to get contributions of copyleft source code rolling back in to the FOSS ecosystem to make it unstoppable and he knew full well that most software is produced and consumed by businesses. So, yes, RMS fits the mold; he needed capitalists to adopt Free Software wholesale but failed to foresee how one-sidedly exploitative the relationship would eventually be.

If you disagree, please explain how RMS and/or Perens do not fit the mold.

I think your analysis is too simplistic.

Stallman cared / cares mostly about user freedom, but was canny enough to understand that businesses would also been to be able to engage with this freedom too.

Copyleft licensing was put in place _because_ commercial exploitation was expected. It was designed to preserve user freedoms.

Compromise was built in the model.

But the unexpected twist was cloud; which broke the safety mechanism.

This is the reason I feel it's unfair to say that proponents of the movement are naive. Exploitation was predicted from the outset. A complex turn of events drew the shape of the current landscape.

And if blame is to be apportioned anywhere, it should be firmly at the feet of the corporations profiting.

As an aside, the first unexpected twist was actually Tivoization.

But, anyway, I do not think your analysis captures the situation in the right way. The free-rider problem, where users contribute no/negligible code or money back to FOSS, is the heart of the exploitation; Tivoization or cloud SaaS-ification are merely forms of free-riding. Other forms of the free-rider problem would have eventually become a thorn in the side of FOSS even if those two things had never happened and there is no way to plug that hole in the concept of copyleft.

And I maintain that was entirely predictable (and it was predicted by many a few decades ago!): there is no reason for a business owner to contribute back to FOSS when not contractually obligated to do so. Like the fable of the scorpion and the frog, even if it's valid to do so it's kind of pointless to blame capitalists for doing what everyone knew what they were going to do all along.

But I don't agree that the onus should be on the open source movement to accept blame.

These corporation are not run by people who have no choice, they're run by people who choose to run the system to the absolute limit for absolute material gain.