Just wait until banks stop giving carbon offenders credit, interest or loans when monthly personal carbon footprint limits are exceeded. You'll see the usefulness then /s.
You're writing as if this is a bad thing, but this sound like something that climate activists would actually support? It's basically ESG investing, but in reverse. Rather than trying to affect change by boycotting companies with a bad climate track record, you're trying to affect change by boycotting people with a climate track record.