So you're excluding deploying/maintaining Open Source Software as a service. That basically excludes how Open Source is supposed to get monetized.
Is it? This means that incentives would be wrong, because then developers would be incentivized to produce difficult to use (but useful!) software - with various poorly documented features, multiple ways to solve the same problems, poor and inconsistent UX... Oh wait... </s>
I am sorry Redis labs got the heat for their license change and I really hope some solution crops up. I appreciate opensource, but I am getting tired of poorly implemented systems, just because there is no incentive to do it differently.
I think the solution lies in "free-to-use (but not free-to-sell), source available" licenses. I haven't seen one that would convince me yet, but I am certain that with big-tech companies behaving like they do, more and more developers will think twice before giving away their work for free just so others can make billions off it (and take away income from the very companies providing bread and butter to FOSS developers - coughAWScough).
Keybase, Inc. https://en.wikipedia.org/wiki/Keybase
The money always comes from somewhere...
The answer is, sell support.
Note that RedHat, often quoted as success story, is really a services company that just happens to write an occasional piece of software, and support them when their customers need it.
They do? Maybe. But they are walking a thin line between their short term (make it complex so we can, you know, sell support) and long term (make it simple enough that people don't jump ship) commercial interests. This is the reason I call it "unnecessarily" complex - it is in the interest of companies who sell support services that the product is not as easy to use as it could be.
Do we really need this? I think not, and I actually prefer what Redis Labs, MariaDB and others have been doing with the licenses for their modules. Sure, Business Source license and similar are not open-source (as in "freedom to take the product you have built and sell services on top of it, driving you out of similar business as collateral damage"), but at least they provide developers with the incentive to produce easy to use software, and not just because they feel like it, but because they can actually earn their living from it.
There might be some exceptions that "make it work", but this is in spite of just selling services on top of their product, not because of it. The cards are stacked against them - it is much easier (and profitable) to take other persons' product and build on it that it is to build your own.
In my experience, selling support is an acceptable answer only in the eyes of would-be competitors. Otherwise it is just plain wrong. </rant>