Worthless? I can print out a trillion ton carbon credit on my printer. I should be a billionaire, at least.
There is notional value and there is market value.
There was a guy with a web page some years back.
He had or worked for a company that cleared land, for development, to clear trails, whatever.
He, for a while, sold carbon debits, based on the number of trees he cleared.
At least that was no scam.