Training costs...
A quick note regarding endorsement training costs...
In normal times a pilot will stay on a particular type for five years, then perhaps return as a captain later. Aircraft typically stay on the books for twenty years, so you can see that a normal airline (ie, one not frozen in time by a failed ideology) would perform at least four cycles of endorsement training.
On a per aircraft basis, thats around 45-50 pilot courses. Airlines make a profit charging the unfortunate $30K for a course, so by that metric initial training, over the life of the airframe, is $1,500,000, give or take. Each aircraft should be able to generate > 1 Billion in revenue over 20 years. So the initial training is 0.15% of that number.