You are not the first one either. I saw a political thread yesterday (
https://www.airgunnation.com/topic/will-all-the-new-anti-gun-legislation-being-proposed-affect-us-in-the-air-gun/ ), started by an account that had no activity on the thing for two years. It appears that the hacker created two random threads, then started the political the thread.
https://www.airgunnation.com/members/locker50/forums/ There have been a lot of random threads started lately by new members seeking member's to voluntarily give personal information about themselves and the hobby.
Read into this what you will, but there are only a few types of entities with this type of ability to hack and start all of these threads lately. Generally, one is a government party/employee seeking information to push their political agendas, and the other is a business with malicious intent in stealing personal information to use as they see fit but without your knowledge or consent.