[dd82]

Given current academia which puts a significant negative on discussing why research failed, I doubt your idea of post-mortems, public or private, will gain any traction.

https://academia.stackexchange.com/questions/732/why-dont-re.... seems to list out reasons why not to do postmortems

[anonymousDan]

There are some venues, e.g. this Asplos workshop: https://nope.pub/