[Guide] MOTE6 Earthquake

Unless it changed, I think the minimum post requirement to become a non-manually awarded TL3 was to reply to 10 different threads in total. There were other requirements of course, but making posts was very modest requirement.

New Forum Guide - Syntax & Features - General Discussion - Diablo 3 Forums (blizzard.com)

Some of the requirements noted in the link above definitely became less in mid-August.

For manually awarded TL3s, one of them has 22 post total where 2 have occurred since April 2020. Another manually awarded TL3 has not logged in over 4 months and last post was in August 2020. Therefore, it would appear that there is not a high bar for posting to maintain TL3 for either manually awarded or met through forum requirements.