They just hide your submissions/comments beyond your 1000 most recent contributions from your profile. The contributions remain on the website. I’ve found the only method to find contributions beyond the 1000 limit was to Google it or use third party archive databases.
With the new change workarounds to find old contributions will not be needed.
Interesting, tell me more please. I presume it requires loading a different OS image as standard iPhone/android OS images will pause apps and attempt to go into a deep sleep after a long enough period?