> This doesn't apply as much to Redis Labs since they swooped in much later, but the general principle of trying to monetize your project with source-available licenses doesn't feel unethical to me.
Yes, monetizing with a proprietary license, whether source available or not, doesn't seem unethical to most people outside of Free Software ideologues.
“The licensing model isn't unethical but competing ones are” isn’t why open source licenses became popular over proprietary (including source available) licenses, the fact that they commoditized the underlying software, enabled competing orojects evolved from the same codebase on essentially equal terms (which also allowed a competing project to fully replace the original if the original at some point failed the community) and, as hosted offerings became more common, the zero licensing friction for hosted solutions, that's what did it.
It does mean charging monopoly rents for a hosted service isn't a viable way to recover development costs and pay returns to VCs, but until fairly recently, no one was trying to do VC-backed startups around single open-source products with that as their whole business plan, and the arguments as to why that would be a bad idea were well developed by the mid-1990s