One thought is the lack of read permission for Rules.
The other is that I’m unclear if the scope is the same when using a SmartApp token. Certainly Rules created in apps in Glitch only appeared in the app they were created by, but that was a long time ago.
I thought I was remembering it right. I don’t find it particularly remarkable as WebHook Endpoint apps are largely used for automations and I’d expect them to manage their own private set of Rules. They aren’t really acting as ‘me’, they are acting as themselves. Well I know what I mean, I just can’t express it.
The documentation suggest that there is a limit of 100 Rules for ‘User’ and 50 Rules for ‘ISA’. I suppose ISA could mean installed Smart App or something like that which might suggest each instance of an app has a limit. Whatever they mean it makes you wonder where the 200 Routines limit materialised from.