We do collect this data.

I personally don't put a lot of stock in these kinds of metrics because they depend far too much on the way specific teams operate.

For example perhaps Copilot helps developers understand the codebase better so they don't need to break up the tasks into such small units. Time to PR merge goes up but total coding time could easily go down.

Or perhaps Copilot works well with very small problem sizes (IMO it does) so developers start breaking the work into tiny chunks Copilot works well with. Time to PR merge goes way down but total code time for a feature stays the same.

For what it is worth I do not believe there have been any significant changes with these code level metrics either at the org level.