And the 777 is their real money maker and desirable product. It's the last engineer led Boeing plane and a damn near perfect sub-sonic trans-atlantic carrier. Overbuilt, but not a maintenance hog, economical, flexible in routes options and interior design, and ironically: ideal for a non first class international travel market, since truly rich people fly private now, so most international outside of Emirates has gone to business, premium economy, economy as a 3 tier design.
But it's long lifespan is more a product of General Electric's absolutely genius engines than anything else.
Those genius engines are the downfall of the MAX: the low slung wings don't really accommodate such big, efficient turbofans, so they had to stick them way out in front of the wings, upsetting the balance of the plane. Boeing tried to fix it with a software flying assist program. It, er, didn't work right.....