The tradeoffs you cite aren’t about the CAP theorem. It’s more about RUM conjecture: http://daslab.seas.harvard.edu/rum-conjecture/
Seems the same is playing out out in Postgres with this extension, maybe will take it another 20 years
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I am wondering, why it took so long for something like this to happen for Postgres, where as Vitess existed for MySQL more than a decade. I am not an expert, but I hear Citus is not really a fair comparison with Vitess.
"They still have cereal and fast food and they're not getting shot so they're fine." LOL.