Not so sure about this. At scale, sure, but how many apps are out there that perform basic CRUD for a few thousand records max and don't need the various benefits and guarantees a DB provides?
I'd also be hard pressed to find any real reason to chose CSV over JSONL for instance. Parsing is fast and utterly standard, it's predictible and if your data is really simple JSONL files will be super simple.
At it's simplest, the difference between a CSV line and a JSON array is 4 characters.