I'm an Android user, and a little less than a year ago I actually bought an iPhone, specifically due to Apple's iMessage lock-in (nearly all of my friends have iPhones, and the especially broken group messaging between iMessage and Android was the primary driver of my desire to get an iPhone).
Except the problem was that, after over a decade on Android, I had zero desire to switch over all of my data and apps over to iPhone. For better or worse the "Google ecosystem" is where all my stuff lives and I just didn't have a desire to spend a bunch of effort just to switch. I ended up giving the iPhone as a gift to an iOS-loving family member.
That's the thing about both iOS and Android platforms - I think you'll find anyone who has been in those platforms for more than a couple years will be extremely reluctant to switch just due to the effort. Our cell phones are often the center of our digital lives now: apps, headphones, watches, etc. The lock-in I think is more from that "ecosystem effect" than any amount of particular lock down.