Complexity can't be destroyed, only moved around. For a great number of tasks this solution offers a bad set of trade offs.
But, at a certain level of scale everything is a data engineering problem, and sometimes this is the (relatively) simple solution when viewed in the context of the entire system.
'Just use mySQL/SQLite/Postgres' is great advice until it isn't.
Every problem has an amount of essential complexity, which as you said can’t be done away with. Imperfect engineering often adds unnecessary (accidental) complexity.
I think it would a mistake to approach a domain and assume nothing can be made simpler or more straightforward.
But, at a certain level of scale everything is a data engineering problem, and sometimes this is the (relatively) simple solution when viewed in the context of the entire system.
'Just use mySQL/SQLite/Postgres' is great advice until it isn't.