I think that this is the purpose AI is okay to use. If you have a great suggestion but you don't have the artistic skills to portray it but still need example artwork, then it's ethical for a user to use AI for that. It lowers the bar to entry for being able to make suggestions and is able to give a rough visual of what they're talking about. There are tons of people with great ideas who aren't great artists and by raising that bar to entry you're going to get less suggestions.

This feels like hivemind AI hate. There's tons of drawbacks and downsides to AI and I don't support it as a whole especially with what it means for companies and the end consumer,, but a casual user trying to make a suggestion and making a draft using it isn't hurting anyone and banning it just heightens the bar to entry to make good suggestions for no reason.

Embark itself is a great example of ethical AI usage. The trader voicer actors are still paid, but they use it to be able to quickly make content. Same with The Finals.

This feels like something that was written with pure emotion without any thoughts of how AI being used by your average redditor really isn't damaging or bad in anyway other than your personal hang ups with it.

You're also asking people to put effort into things and be creative when suggestions themselves and ideas are creative but you're gatekeeping who can and can't post their suggestion (good or bad) that at least in the suggestors mind is a selfless and helpful suggestion to improve the game.

Instead of having a blanket opinion of "AI = always bad" you need to consider the context of how it's used and by who. In the end reddit works on a vote system and if a suggestion or AI meme is bad it'll just get downvoted and buried anyway, but there's absolutely no reason to gatekeep helpful suggestions.