I have removed Modify All Data permission in System Permission for one of the permission set. But, what I am seeing is a weird error which I dont have any clue to fix it. I searched everywhere for the solution but in vain. I am a system administrator but still I got this error. Please see the screenshots below.
Additional Info: I have just found Journey Builder Events and Journey Builder CDC Events are all related to platform events and resides in a managed package. But, I dont know why I am seeing the error related to platform events when I tried to update the system permissions.