I don't think it would be as big. BOS is a lot richer per Capita and at the upper income levels and attracts a lot of foreign tails and premium flights as a result.

PHL currently has the only US carriers, Air Canada, BA and QR. Without an AA hub, you likely lose QR. BOS by comparison has EI, EK, LY, AF, BA, HA, IB, JL, KE, KL, LA, LH and more.
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