Can you elaborate on what we have seen? Modernization in quotes suggests that Apple wasn’t successful.

I put modernization in quotes because in most cases it was really a shim placed ontop of the existing Objective-C API that changed some names or parameter types; so, in this case it wasn't quite as extensive as a Java->Kotlin transition would be since Objective-C already supports many "modern" features such as closures.

What does "already seeing this" have to do with any meaningful input on the subject?

I was providing a parallel from my experience, which I thought might foster discussion on how such an API improvement might proceed based on historical anecdotes. Was this not a welcome addition?

i think people are interested in the lessons learned in the past. are you sceptical or hopeful? how did apple's stab at this work out in the past? is it fundamentally flawed or deeply overdue.

I think Apple did a pretty good job in most cases when getting their code to work well in Swift. I'm hopeful that this will also be the case with Android, but the hitch is that a lot will have to change. Swift's closures, extensions, etc. already had Objective-C counterparts which were not difficult to translate; but Java, on the other hand, doesn't provide many of the features that Kotlin does (hence the drastic reduction of boilerplate we can see in the blog post).

I thought that was purely just Swift's own translation layer to make Objective C APIs more Swift-y, not an API change.

There were API changes to make the translation happy, in many cases where conventions weren't being followed strictly.