And not by opensource.org's definition, which prohibits use restrictions. It's not reasonable to act like OP is being idiosyncratic when this fails to meet the protected definition of "open source".
The term "open source" is not protected, the OSI (opensource.org) attempted and failed to acquire a trademark on that term.
Fair enough. Is there any shared definition of "open source" which permits use restrictions, then?
I admit not to have read the whole paper, but in the intro nowhere do they mention “open source”, so it seems unfair to measure them by that definition