Technology

No. The "Contract of Carriage" that airlines create between you and them when you buy a ticket explicitly disclaims any liability for stuff like that. Delta's for domestic flights has, under "Rule 2", the following:

Delta will exercise reasonable efforts to transport you and your baggage from your origin to your destination with reasonable dispatch, but published schedules, flight times, aircraft types, seat assignments, and similar details reflected in the ticket or Delta’s published schedules are not guaranteed and form no part of this contract. Delta may substitute alternate Carriers or aircraft, change its schedules, delay or cancel flights, change seat assignments, and alter or omit stopping places shown on the ticket as required by its operations in Delta’s sole discretion. Delta’s sole liability in the event of such changes is set forth in Rule 22. Delta is not responsible or liable for making connections, failing to operate any flight according to schedule, changing the schedule or any flight, changing seat assignments or aircraft types, or revising the routings by which Delta carries the passenger from the ticketed origin to destination.

Source: https://www.delta.com/us/en/legal/contract-of-carriage-dgr (click the "plain language PDF" version)

Every airline has basically the same contract. They can do whatever the fuck they want as long as they get you from A to B. They don't even have to use a plane, or get you there on time.

My guess is most airlines have clauses in their terms and conditions that allow them to change the aircraft type without prior notice. Pretty sure their lawyers would argue that this is considered a management right for operational reasons.

But I'm no expert 🙃