Currently it is possible to select the Activity entity from the list of available entities that would trigger on "when a new record is created". But at this point is is NOT able to trigger.
In Flow (Power Automate) we want to be able to trigger a flow once an activity was created/updated or deleted.
The Activities entity is refererring to the activitypointer table for Dynamics 365.
We don't want/need to create a flow for each activity type in the system. We require to track and respond to all activity related actions.