I guess I'm like one of the 5 people whose behavior will be affected by this. I fly ~40 segments a year on DL for work and maybe another 8 or so for pleasure with my family. Whereas before I would usually choose DL Basic Economy for those pleasure routes over WN for domestic travel, that's probably not going to be the case now. For international travel it's pretty absurd that a $1300 Basic Economy fare to AMS isn't going to count towards status. Just picking a random date for next May the difference between Basic and Main is $150. For a family of 4 that's $600. I think I would rather fly UA and at least have it count towards status. C'est la vie.