Whether someone here confirms it or not for their own travels, the fact of the situation is that people do travel on intra-Scengen flights with expired Schengen visas, expired residence stickers/cards or with passports having stamps that make it seem like they have been in the Schengen zone for more than 90 days within any 180 day period. If any or all of that is a problem during the course of intra-Schengen travel by air, it's a very infrequent problem for persons in such categories.