Having used “REST” for 10 years or so I can confidently say I’ve never used REST
1. Ancient XML/SOAP based APIs Frankenstiened to use JSON
2. Poorly implemented RPCs advertised as "JSON REST API", usually the entire thing either relies on POST requests but sometimes GET is used to make stateful changes.
3. Things that should obviously be RPC split into dozens of anemic JSON endpoints that the caller has to re-construct to get anything useful
Incidently, my company's leadership got inspired by Amazon's API culture and made # of APIs a metric that teams must hit. The result is every single endpoint being deployed as a separate API, and teams blocking access to native vendor APIs so each operation can be republished as a new API. :)