opinion As an email server admin I am close to blocking an extension

Look at the purpose of the extension. From what I am reading, .BID is primarily used for auctions. If you sell anything (including domains) on your server I would not ban this.

I would still be hesitant about banning it if you don't sell anything. The only solution I would use is some bot that automatically replies to any incoming .BID emails that their traffic is banned and they must send mail with another domain extension.

You are not alone.
.bid indeed seems to be bad neighborhood.
The odds that you will receive a legitimate mail using that extension is nil imho.
I think you can aggressively and safely block this stuff