That's why I said "kinda retconned" ;P
I am aware that most of the backstory was already there.
I don't know, the character of Yondu just doesn't work for me across both films. He's too much of a murderer and a scumbag to be likable. And in Vol 1, despite that particular line, I thought the relationship between the two was way too antagonistic to suddenly transform into something so heartfelt by the end of Vol 2. Yondu felt like a secondary character in Vol 1 that Gunn fell in love with once the movie was done and decided to push as this integral part of Vol 2. Hey, maybe that was the plan all along but that relationship just wasn't believable for me which led to the entire emotional payoff off the film falling flat. His whole arc with the Ravagers and him being such a beloved figure as proven by his funeral also felt super forced, he never really earned that kind of respect prior to the very end of 2.