JSONL is often better if you can spec that from scratch, but, sadly, still has somewhat poor support in a lot of environments that support JSON. I've had the most problem with interacting with people using environments that are "helpful" and aren't really programming languages, and I usually end up having to offer them a plain array anyhow.

This can also be helpful when you're outputting, say, a 10MB JSON object, which isn't necessarily that large anymore, on a server where you'd like to not have to allocate 10MB of RAM to it. You can stream out a plain ol' JSON object without the resource usage.

Sadly, it is indeed easier to convince environments to stream JSON out than it is to stream it in.