Maybe someone can enlighten me.

In this case if the OP is seeking “Justification”, it’s a poor goal:

1. What is the purpose of opening this thread? To blow off steam? To line up on your side? To try to embarrass/pressure the Agon moderator to get your way - an explanation? We do not know the “Justification”.  
2. Agon makes the rules, we are not “entitled” to an explanation 
3. The Agon moderator has little incentive to explain their actions - more work and possibly increased grief

It’s best simply tone it down and move on.

@audphile1 +1. Thanks for the clarity.

@secretguy definition of spam…

irrelevant or unsolicited messages sent over the internet, typically to a large number of users, for the purposes of advertising, phishing, spreading malware, etc.

In an audio forum this message you posted

Congrats and I feel ya. The current state of the country has stolen most of my joy.
 

is irrelevant and unsolicited and is sent over internet to a large number of users, advertising your political views. 
 

It’s hard to argue with the action taken by the moderator. I get it you don’t like it. If you feel like expressing your political views you can do so on public property as a protest. If you do it on private property, which is conceptually similar to doing it on this forum, you will be removed. And it could hurt more than just emotionally. 

Sure nothing to do with any of those 4 reasons. But they probably figured it would generate political 'debate'. In that case, they should add that to the list of reasons.

@secretguy lol welcome to the club of unexplained comment removal. People have pretty fragile feelings here so report on whim and moderation team doesn't double check but just decides to agree with the person reporting all the time

I've had some harmless, no insult comments deleted. Just received a message yesterday of that manner.

That will be my 21st email alerting me of a removed message. It seems like a common occurrence for me unfortunately and I can share all the messages nuked if people think I am lying about not insulting anyone

"So what was my infraction?"

Choose all that apply. When finished, self-flagellate with a birch branch until you are rehabilitated.