Did you say the same when you heard of MongoDB? that you want NOSQL on SQL, instead of "proprietary" JSON and JS code?
Then we put sql on top of data lakes with things like big query, spark structured streaming, Athena etc.
Then we put sql on top of streaming systems like kafka with ksqldb.
And on top of search engines etc etc...
He's not wrong... Sql is easy, easy is good.