There are still plenty of materials out there which mention try.
This was always going to be a problem with the edition but it’s one thing for some old things to not compile and it’s quite another for them to swap their meaning entirely.
Purging from the “collective memories of Rustaceans and Rust materials” is not something that easy.
Edit: Basically, Rust 2015 is still going to be around, materials written for it will also still be around. Python 2/3 have similar pedagogical problems, I strongly wish to avoid those.