which is strange - imageinfo doesn't seem so complex as to require a continuation, but that's a separate potential issue
iilimit is documented as having a default of 1 [1]. Similar modules usually have default limit of 10, I'm not sure why imageinfo is different.
(Of course, 10 is still too low for practical usage. I think this is so that testing doesn't cause unnecessary load and that everyone is expected to use xxlimit=max in production.)