The FAA, due to extreme staff shortages at some of the largest US airports, is “encouraging” airlines to cut about 10% of flights out of New York. Washington D.C. is also affected. Presumably short haul flights will go away disproportionately. Will AMTRAK be able to capitalize on this? Or will Bus companies? Maybe cars will win out? I think due in large part to capacity issues already being seen in the NEC (where more and more Regionals are running with 10 cars in April) AMTRAK may not be able to handle too much of a boost to the NEC, but State Supported corridors (especially the Keystone and Empire) may be able to handle more slack. High fares on the NEC may push more PHL-NYP intercity traffic onto the SEPTA/NJT route.
Amtrak will probably see some bumps on the margins. One thing to bear in mind, however, is that EWR, LGA, and JFK get a lot of connecting traffic (I regularly run my flights from VA to FL via NYC because of the
really nice airline lounges there, plus NYC-MCO/FLL being "meal flights" on Delta).
The airlines could probably fix a lot of the resulting capacity pressure by nudging connections away from NYC: AA has PHL (and DCA, though that's mostly only going to be good for moving LGA flights); DL has BOS, DTW, and ATL (and RDU's a focus city); and UA has IAD (and arguably ORD). The main thing they
might want/need to do in order to make this work would be to fiddle with faring restrictions (e.g. DL could add BOS, DTW, and/or ATL as an option for some routings that might normally disallow them as a connection; alternatively, they could pull NYC as a legal connection and sub the others on some fares). Taking an example, here's Delta's allowed faring for BOS-WAS:
1. BOS-CVG/DTT/NYC/RDU-WAS
Stripping out NYC from that list (the route is run nonstop, after all) wouldn't utterly complicate things.
Here's another example, BOS-RIC (BOS-ORF is identical):
1. BOS-DTT/NYC-RIC
If they were to re-allow BOS-ATL-ORF/RIC (this was permissible pre-pandemic, up until DL "hubbed up" Boston, probably due to ORF-NYC being split between JFK and LGA and making connections "touchy") and add in BOS-CVG-ORF/RIC (regardless of any nominal routing-length violations), that could divert some traffic (even without disallowing NYC as a connection point).