Elastic (and Mongo and RadisLabs) are trying to do something new.
Linux, without doubt, "reaped the benefits of open source, including free work from the community," to the point where although the original release was 100% Linus's own code and arguably "Linus's software", these days to a first approximation _none_ of the code is "his". The percentage of the ~27million LOC that is "linux" these days that were personally written by Linus is effectively zero.
Elastic is a company paying 500-1000 employees who I suspect (but haven't checked) contributed the majority of the code rather than it being "free work from the community". (And their ability to relicense the code suggests that any community contributed code was contributed under their CLA which meant the contributors explicitly granted Elastic future rights to relicense those contributions, so it's not like the "community" can pretend they didn't know this was possible.)
I don't know that Elastic's business model will work. I don't think there's any guarantee that it will. Part of me kinda hopes it does, because I suspect that the business success of "company backed venture capital funded free-as-in-beer software" might result in more and better software being available to use - perhaps software on such a large scale that "scratch your own itch" motivations have insurmountable ramp up difficulties. I personally think the jump[ from AntiRez's "scratch your own itch" redis, to RedisLab's "Widely Fortune500 adopted and enterprise ready Redis" is not a thing AntiRez wanted to stick around and do. And the world _might_ be a better place for the existence of the non-OSI approved software under license like RedisLabs "source available" one.
It'll be interesting t watch this play out over the next decade or so...