Um hmm. Try doing it now. Most airlines that fly 747’s are getting rid of them or already have. Many that fly the 380 are seriously considering leaving them grounded after COVID and that includes Emirates. The 787 is replacing most international wide bodies and it doesn’t have a first class option. Almost no airline is ordering the A350 with first class. American Airlines still flies 777-300ERs with first class seats but they are the only domestic carrier that does. So unless you want Fedex to build its schedules around American Airlines 777-300ER routes, (right now they only fly into London), the whole international first class option is rapidly going the way of the dinosaur. Dying on that hill seems a bit pointless.