First international flight to include 0 baggage items

I just had the unpleasant surprise of finding out that apparently with Iberia, no baggage is automatically included.

My flights that cost me €20 less than the alternative options just cost me €100 more as I obviously have baggage. In other words the cost of my flight just went up by 25%

Out of the dozens of international flights I've taken I have never heard of an international flight that includes 0 luggage pieces, and everywhere on the site they reference a limit of 23kg but only display the baggage count in a sub menu of the site.