Yep, no doubt what's going on here, they indeed hired bumping service. They are doing it on the light schedule though, probably bought one of the smallest "packages". Anyway, Moss.earth has been added on the list.
Some of the topic posters were spotter posting on Reapchain (Nr.60 in your list), so there is no doubt bumping service is used by Moss.earth.
Huge amount of bumping accounts are also spamming Reapchain ANN for months now. Activity there is one of the major red flags that account is used for thread bumping. Once they get tagged, they just activate new ones. Rinse and repeat.