I have removed that release date from TMDB since it is not the first release (and I don’t see it as vandalism, I personally see it is correcting bad data).
Regarding release dates, these are based on your library settings for language.
As to the correct dates being shown, we had an issue with our current IMDb ingestion pipeline where all release dates were January the 1st as the data was not available. We are in the process of moving to a new IMDb ingestion API which will allow us to have release dates from IMDb. In the interim we switched to pulling release dates from TMDB which is why it is easier to see “less than desired” release dates.
Looking at TMDb it appears they return the earliest release date (regardless of country) to the website when viewing it. Plex allows you to have release year localised to your library language (country) in the new agent.
