My main takeaway: GraphQL moderately improves developer enjoyment (DevEx) by majorly increasing the cost of making production ready APIs.

I've worked on bigger teams where the job was boring and there was plenty of spare capacity to improve DevEx. Spending a lot for a more enjoyable DevEx was worth it to retain good talent. They typically spent about 50% of their total capacity on DevEx and technical debt. Those teams would probably benefit a lot from GraphQL.

Other projects it's just me building an entire product with extremely tight timelines. Or it's a small team without a lot of spare capacity. I probably won't elect to use GraphQL in that situation.