I use GraphQL all the time in conjunction with PostGraphile https://www.graphile.org/postgraphile/ https://www.graphile.org/postgraphile/ and let me tell you, i

I use GraphQL all the time in conjunction with PostGraphile https://www.graphile.org/postgraphile/ https://www.graphile.org/postgraphile/ and let me tell you, it's definitely not slow. If anything it is very fast. But just like REST or anything else, if you do a poor implementation you will get a poor result: garbage in, garbage out.