It is crystal clear.
There is no doubt you can log it.
You can log anything you like.
It is 100% legal to write in your logbook that you flew as a passenger on Easyjet.
I know a bloke who logs passenger time in spamcans.
You just cannot use those entries towards any known pilot license or rating etc (because you haven't got a Type Rating for the plane).
What is illegal is to use log entries towards stuff which the credit is not applicable to. For all I know, your 737 cockpit time might count towards some Indian flight engineer license
Peter337 that is 100% correct without question