What can i do if 1 guy mass reports LFG posts?

Look for group posts are only meant to ask for people to play with, nothing more. Any additional information that looks like buying or selling (even for in-game currency) is strictly prohibited.

80%+ of the posts on the LFG are exactly what I did and they never get banned? It’s exactly what that LFG is used for most of the time

And if they get reported then they'll receive a suspension as well.

As ngocphi has said,LFG posts are for finding people to play with & that's it.Trading of any kind,even for in game currency,is not allowed.

Its better to post LFG post in groups. People respond to those

I'd agree.. except a large number of LFG posts are
spam, as I originally posted but somehow was missed in response. Outside of Report to Xbox Live Enforcement (which does little to curb the abuse), there is little in the way to clear or filter out the spam LFG posts. If LFG's are mostly
spam, what is the purpose of having it? I don't think the LFG purpose is to get people to follow you, sell a dlc, sell an account, scam out in-game cash, etc. But that is what is has become. So, again, what is the purpose of LFG other than to browse thru spam?

Yes, trading in the game is allowed, but LFG posts are not in the game. You can only use in-game mechanics to trade.

Which is all that I did

Not according to your own words:

"I only posted in an lfg private group to TRADE exact word we’re looking to trade my demon crazy guy and old man masks."

LFG is literally only for looking for other players to play with. Literally anything else (trading, selling etc) is not allowed on LFG posts.

You can trade in game but anything posted on LFG regarding anything except looking for others to play with can result in a suspension.

Yes, trading in the game is allowed, but LFG posts are not in the game. You can only use in-game mechanics to trade.

Which is all that I did

Not according to your own words:

"I only posted in an lfg private group to TRADE exact word we’re looking to trade my demon crazy guy and old man masks."

LFG is literally only for looking for other players to play with. Literally anything else (trading, selling etc) is not allowed on LFG posts.

You can trade in game but anything posted on LFG regarding anything except looking for others to play with can result in a suspension.

All trading in that game is done through trade group posts. The entire Xbox live page is dedicated to it and the lfg 76 group every post in both places is to trade in game items u people obv do not play fallout 76