[clarle]

iOS development has been around for quite some time now. Most senior iOS and Cocoa developers probably started with Objective-C before slowly migrating codebases over to Swift.

[martinclayton]

I think this must be it, or at least this is one story that fits.

Seems a shame that people report Objective-C experience as Swift experience to such a great extent. These surveys are not resumes...

Perhaps it just "proves" that all data in these charts is questionable.