Why can't I reasign the "Undo" function as ctrl+y instead of ctrl+shift+z. Why can't I remove the default "yank" command

R-Studio version 1.2.5001. Now you can.

By default, Redo is now linked to CTRL+Y. However, it still doesn't work, as it (still by default) conflicts with paste Yank text.

To make it work, go in Tools → Modify Keyboard Shortcuts → Look for Yank→ delete the conflicting assignment that uses CTRL+Y. Make sure that Redo has that instead.

Kudos to this question that highlighted there could be a hidden conflict, specifically with this "Yank" thing.

I concur... There's supposed to be a filed bug report for that...

https://support.rstudio.com/hc/en-us/community/posts/208103438-Redo-pastes

In the meantime, CTRL-SHIFT-Y works fine, although it's probably not what you're looking for.