For me it would take a lot to change.Both great phones, ultimately just comes down to OS preference. Hardware is so good today, software and services are really going to key difference. For me, I look for the best overall combination of performance, security, privacy, ecosystem, apps, and support. Apple currently gets my money, but that could of course change.
It's taken a long time to get my devices, media, and their implementation incorporated in my every day life.
Many have told me it's easy to convert and that many features of the iPhone are the same on the galaxy, but the galaxy allows for more customization. Not a big enough reason.
Both platforms are excellent depending on the user's needs and desires.