Мафия 10. The Experiment.

I'll express my opinion based on my experience.

Now, let me explain. Every night, I had to wait for someone to send their Night Defense (ND), meaning that 24 hours always passed strictly. This was quite annoying.
That night, I eliminated everyone who hadn't sent their ND. Perhaps I acted unprofessionally, but it was my decision.

This is more than unprofessional. But it also contradicts the rules. So, you violated them yourself? At the same time, you "killed" Cash within the rules (formally speaking).
Although

(as far as I remember, there was such a clue on TaCo in Mafia VI)

The person received a green nickname – a minority nickname. Most nickname holders have blue nicknames. It's silly to say that you can give a clue on a blue nickname because most players "follow" it.

"third" round was replaced with "fourth"

This is just nitpicking.

"it's just the beginning" was replaced with "recording"

This can still be excused as an argument, but again, it wouldn't have been difficult to tell the town that there was no such clue. (besides, it seems to be true anyway)

In general, I wasn't wrong when I wrote before the game started about your unserious attitude towards your own idea.
Well, okay, the newspapers resemble gaudy, mismatched colors (like, original, maybe), but your actions, and especially their explanation that you were simply bored, are not serious. I'll repeat once again – the GM must be serious because they are in charge of the process.

P.s. If the conversation turns to the incorrect placement of my post (since I didn't participate in the game), I'll move it to "discussions," although it doesn't change the essence.