Like many domesticated animals, budgies have been bred over many generations to give preference to features that appeal to people, with much less regard given to how these practices may affect health or longevity. As much as I love British bulldogs, they are a prime example of this phenomenon, they suffer all sorts of respiratory problems and often can’t even give birth to puppies without veterinary intervention!
My Valentino is not a show budgie but he does have some features that suggest he may have some in his ancestry. He had several vet visits last year with a very weepy and irritated eye, which we originally blamed Lilly for since they’d not long had a big fight over her food and we thought she may have scratched his eye. Turns out Val has a few tiny feathers around both eyes that sometimes encroach on his eyeball and cause irritation, which isn’t surprising really considering what a big, boofy feathery head he’s got. I suspect his extra feathery head is a throwback to an exhibition budgie somewhere in his past. His head is not as big and boofy as a full show-type budgie but certainly bigger than his wild cousins!