If the goal is to monetize the Redis Labs modules, why not just put them under straightforwards proprietary licenses? This is a well-trodden and well-understood path.
This Commons Clause combines the twin mistakes of being both offensive and ineffective. It will get Redis pulled out of many OSS repositories, decreasing your distribution and mindshare. At the same time, I can see Amazon and Microsoft lawyers laughing at it now; it will do zero to prevent them from building their own cloud offerings.
I really have to wonder about the quality of advice that FOSSA is providing to its clients if it went ahead with this. You say 'OSS-savvy companies aren't dumb' but it seems like the consultants of FOSSA are, or they are counting on everyone else in the industry being gullible.
(and before you play the "consider the poor OSS developer" on me, I worked on Postgres for 18 years, and we never pulled this kind of nonsense)