Why are apples typically grown as central leader instead of vase?

It doesn’t really matter how you manage the trees for the first 30-50 years, it becomes natural for most varieties of old apple trees to become open center trees if you want them close enough to the ground to harvest and prune without much ladder work.

Your problem was probably excessive crop load- I manage hundreds of old apple trees trained to open center and crop load rarely causes branch breakage in trees pruned for strength (not excessively lanky) if the crop was anywhere near adequately thinned. If such breakage was common it wouldn’t have happened so much in one season- the branches just wouldn’t have been there.

With more experience you will learn how to manage those trees, but pruning them is not something you can master quickly by reading some guidelines.

Managing old apple trees on estates has been the core (pun intended) of my business for the last 25 years- I scoured the NAFEX library for info before I even started and already had years of experience with fruit trees, but the complexities of managing them used to terrify me (deep breathing exercises before work helped). I had to pretend I was an expert to become one- and one day I hope to do that.

Learning the intricacies of managing full sized, old apple trees is a complicated but fascinating story.