I completed a 6-month course at the Word Police Academy in Scranton with top grades. I am fully licensed.

"Eschatological" is extremely obscure, and the vast majority of readers will not understand what is being said. I've seen the word in the wild probably on two occasions in my entire life.

Plus, "doomsday" doesn't need to be synonymous. This particular post was exactly referring to an obsession with doomsday scenarios. The aspects of eschatology relating to afterlife, judgement, salvation, and so on, were not at all the point.