Well Crossair Ltd. is now the Swiss flagcarrier.
The term regional airline is abused by the former SR guys to put the ex Crossair guys down.
The term is actually correctly fitting the environment in the US where there are regionals and mainlines, which operate even partly under different FAR's. Regionals usually are feeder airlines feeding the hubs of their respective mainline. That's why they are sometimes also referred to as commuter airlines.
Because of scope clauses they are usually only allowed to schedule a limited number of point to point flights. The number of aircraft with more than 50 seats they can operate is also strictly limited. Furthermore they are even limited in the total aircraft they can have in relation to the mainlines number.
Crossair has not been an airline like that at all. They were not only offering feeder flights, but also a lot of point to point connections. They had even their own hub at Basel airport and were starting to build one up at Geneva.
Then they have neither been limited in the number of aircraft they could operate nor were there any restrictions in their size. They had a considerable number of Avro RJ 85's and 100's plus up to 12 MD80's. They had their charter operations with the MD's and other types.
Finally the routes they flew have been far from regional: Basel-Helsinki for example or Geneva-Athens, Zurich-Valencia, Zurich-Edingborough, I don't know what's regional about that...
So one can't compare former Crossair with American regionals or commuters and therefore the term is misleading and mainly used to ridicule them.