Meh.
Sure, it's hard to make money in open source. I spent 20 years doing it. It ain't easy.
But here's the thing: open source also helps you accelerate a business you might not otherwise be able to build. You get market validation by giving away a free thing, and then you hope to be able to collect some revenue on the backend once you've got a large enough user base, a proven product, and maybe even some contributors. Maybe even a whole ecosystem. You think VCs would have thrown all that money at a thing with no users?
Want to throw it all out? Fine. That's your right. But it's not gonna stop companies from forking the last open source licensed codebase and taking your cookies.
Open core is a thing. You can be good at it, and users understand and respect it. You would think that Mitchell would have learned after his failure to monetize Packer that he needed an actual proprietary value prop to build around before he built Hashi. Guess not.
You can't have it both ways.