> I don't want to get into a debate about this. I've told you what I believe and why I believe it.

You've told me what you believe, but not why. You just made vague, handwavy assertions about things that you clearly understand rather poorly. Obviously you don't want to debate this, since your arguments are those of a flat-earther trying to explain their views.

> I will add this: if you are truly at a company that has adopted GQL and you are not spending significant eng time on it, you're either not measuring it (ding ding ding!),

This is just silly. You're just making assumptions about things you know nothing about. GQL lets us be a lot more efficient. The libraries for building GQL resolvers make it easy for full-stack devs to build new endpoints, and since modern tooling can integrate tightly with the underlying database technologies, no one is building footguns; all queries that are generated are optimized automatically and there are no N+1 issues. Any frontend dev just writes a GQL query, types are generated automatically and the results of querying the API are fully typed. Every modification to the API can be checked and diffed and we can be warned about recent clients that might be broken by the change. It's not only a breeze; it's brilliant and a joy to work with.

> Perhaps relevant to that point: the complexity of explaining GQL to an unfamiliar developer is not what I'm talking about. Most people can learn enough GQL to make really awesome footguns in a single 30 minute session!

This is even more silly. It's not possible to build GQL query footguns. Whether a query is a footgun is entirely dependent on the underlying resolver. If you build poor resolvers, then someone can build footguns just fine, but as I just explained, this doesn't have to be a problem. You know what is also a footgun? Frontend developers making N+1 requests from the frontend, hammering your API unnecessarily and possibly getting inconsistent data because the multiple different requests aren't necessarily looking at the same data.

> REST is easier because, instead of having to do all of that instrumentation you're talking about across an entire query graph, [..] you have endpoints, which correspond to specific needs, which you can then optimize appropriately on a case-by-case basis.

Yes, and what sort of endpoints do people end up writing? Either they 1) add a bespoke query language via query parameters or some such to conditionally expand nested relations, which I've already explained elsewhere is not-very-standardized, poorly supported by tooling like OpenAPI and in the end just GQL done poorly, 2) they add bespoke endpoints with nested relationships already expanded resulting in an incredibly poor API that takes a dump on REST principles or 3) they just make a bunch of requests from the frontend, which I've already explained is also bad.

What I am describing in terms of instrumentation is no different from what something like sentry can do with any normal REST API(it can hook into and, say, instrument all your express.js calls), except that a GQL schema is an introspectable, "executable" data-structure which automatically contains all the type information you need to make instrumentation great. I can tell you the number of milliseconds it takes to query for every single field in my entire graph. And all this is literally a couple of lines of code,

> (you've described quite a lot of infrastructure there, btw...),

I'm not describing infrastructure for observability. I'm describing the system I'm working on. If you think you can make judgments about our system architecture based on a single line description, I think that speaks volumes on its own. You can do better than this.

> When all you expose is a structured query language that anyone can use, you have made things (perhaps) easier on a single dimension (consistent interface), but you have abstracted all of the other problems and made them harder. And you have all of this other infrastructure to look after now, too.

Now you're just latching on to our infrastructure again, probably because you understand GQL so poorly that you think that using GQL automatically comes with the infrastructure I described. It does not. A simple GQL API is at least as simple as a simple REST API, at least when viewed from the lens that it automatically comes with documentation for your API and a rich ecosystem to communicate with it in well-typed manner. Contrast that with a simple REST endpoint which just returns unstructured data without any type information attached.

I think it's me who has lost interest now, because from my perspective, it is abundantly clear that you've never actually really worked with GQL, and you're just arguing from a place of uncertainty because you're scared of looking into new technologies -- after all, why would we ever change something that works? It's just all hot garbage, right? Or possibly you're just parroting someone else's equally poorly informed arguments that you've read somewhere.

I will extend this little olive branch, however: It's entirely possible to build poor GQL APIs, where some of your arguments would have some merit(if interpreted very charitably), but the reason it's even barely worth mentioning is that this literally applies to everything, and REST APIs are part of that set.