...and not when your destination is not NYC but BOS, IAD, ORD, ATL, etc. Then flying BA is more comfortable without having to switch in the US after a long flight to a short haul pain-in-the-... flight with typical delays / cancellations. By flying BA you get all the way to your final destination (or near enough) in comfort.

I have flown three times with BA in the last 3 months in C for under $3K when the cheapest LY C fare has each time been $3.5K - and that's for W class which gives you the same points as Y and no upgrades. Any BA C fare including the cheap I (around $2500 return) and R fares (around $2800 return) give you full mileage and tier points plus the ability to u/g to first with miles if you like. Frankly BA's C is so good it really is not necessary to u/g whereas on LY the F hard product does not match even closely BA's C product.

There are times when flying direct to NYC makes much more sense and in that case the extra few hundred dollars may be worth it for some but I can't really justify it unless I need to be in NYC on a Sunday morning for example.

No doubt the biggest advantage of LY is last minute upgrades which as a PL you can be pretty sure to get on non-busy flights. I tend to fly however on the typical business flights leaving Sunday or Monday, returning Wednesday or Thursday which means I need to worry about the u/g and follow the loads in advance to see if I should upgrade prior to the flight with a full voucher or not. It's a pain and takes up too much of my time. I'd much rather pay for C in advance at about the same price as LY full S/Y fare and not be concerned about getting C.

I will be sorry to see my PL gone later this year but LY should be sorry to lose about $30K of annual business from me - all they had to do was offer C at similar prices to BA and they would have had my business - it's a shame.