It looks like the flight was not delayed due to a mechanical problem, but rather due to a problem at SEA (fog?). The inbound aircraft for the flight (flight 18 ANC-SEA-MCO) was diverted to PDX on the ANC-SEA leg, and there were a number of other diversions to PDX this AM. As a result, several other transcons were delayed significantly, including ORD and EWR.

Also, as Alaska has the only non-stop service between MCO and SEA, I'm not sure how much time it would save to rebook on another carrier and make a connection to get to SEA. One might get stranded overnight in the connecting city, especially if the connection time is short.