The A321NEO has sold over 1700 frames so far. Define "not enough". You can't talk about the LR in a vacuum and ignore the non-LR variant especially when in a few year all of them will be LRs
I'm defining it in the same way LH's CEO is. You are choosing a different way.
Either way, your assertion that "being a more efficient 752 replacement doesn't seem to be enough
" based on LH's concerns are frankly ridiculous. We know that the 757 is marginal on Germany-US sectors and from Spohr we can assume that in LH's intended configuration performance A321lr would be unacceptable. But efficiency has no bearing on it - if you can't do the sectors you can't do them. The real test will come with operators for whom the extra range will
open up viable new destinations. It's going to take a little while for us to see if that happens - not helped by that fact that some deliveries could be up-sells from other A320 family orders. I'm not even sure why we're obsessing over transatlantic routes either, this isn't 1980. The LR will probably have far more impact in the Asian markets, and I'm intrigued to see its effect in Africa and Latin America.
Also, I don't think you've got quite how much more "efficient" it will be. Fuel burn - sure. You'd expect so. But don't underestimate the benefits of being a member of the A320 family. There's over 8,000 of them out there - when production finishes, probably in the mid to late 2030's, there will be something like 15-20,000 of them delivered. That brings massive benefits that the 757 never had.
One last thing - I know that some people on here view LH's proclamation as proof of the market for the MOM - I'd be careful. This is not the aircraft it will be competing with.