it puts UA at a competitive disadvantage for everyone buying J & traveling from LA to Manhattan.
for these passengers, the LAX & JFK AA Flagships lounges are so much better than United Clubs.
lounge quality is not immaterial when considering getting to these airports a bit early to account for the possible hellish traffic at either end.
perhaps UA is fine with the revenue from people needing EWR and locked-in elite.
for me, i pick UA only if cheaper.