For me the opposite is true. The value of multiple vendors with a similar product is that it drives prices down and liberates me from a lock in. I genrally avoid managed services that are not available from all three major cloud providers, and put abstractions between my suff and their so I can move my workloads around.

As to SQL. Its a weird feeling to read all that; I've spent 15 years working with very large relational databases -- and about 5 years ago I ditched it all in favor of using key-value object stores, wasting some storage but saving a metric ton of manhours of development work. Not looking back.

What do you use for your KV storage?