It takes control the machine to get payment. What other criteria was there?
It doesn’t hijack your data
In my understanding, that is a criterion for cryptolockers, which are a proper subset of ransomware.
Nope... just your computer. Still ransomware.
While the most predominant ransomware are cryptolockers, that doesn't mean that ransomware has to be one to qualify for that label.
Surely you'd agree that this behavior (disabling exit until payment) is malicious in this context...
Malicious for sure. Ahhh the good old times where the App Store actually was checking your apps, and rejecting when it crashed or when they didn't agree about some UI decisions