Ratings would go red unless prices would be lowered, but that would kill your revenues.
So you’d need to re-configure.
Costs for the cabin certainly isn’t a factor, as the required dollars usually should be earned in few days.
But here are some problems to consider:
- fleets with big seats often use Light/BGW aircraft variants and would need a change to Heavy/HGW to cope with increasing payloads or switch to other types
- airlines that operate at the edge of payload/range with heavy/HGW variants would need to look for other types which possibly wouldn’t fit into schedule (cruise speed/turnaround) or are simply unavailable
All this would let you run into either
- type size restrictions
- production queues of several years
- loss of slots
or - in case one would make it - would result in massive overcapacities which smaller airlines in the way of big ones probably wouldn’t survive.
For my airlines that would mean a production queue for roundabout two years, several airlines to be deleted as there wouldn’t be a workaround and lots of work for the CEO - while money wouldn’t matter.
Personally, I consider the “new ORS” to not justify such havok as it is only a little tweak to an existing flaw. Things would be different would ratings and demand distribution receive a massive patch too.