The nuance is financial extraction coupled with deceit.

If your scheme doesn't extract value, nor costs anything to other parties, there is no victims, you can get away with it. Even if policies say no. The risk is termination of service.

Skipping ads is a loss of opportunity for advertisers. But they don't get extracted money. They may not like it, but they can continue to fish elsewhere and aren't being siphoned because you skip their ads.

If you spawn websites and farm fake viewers to scam ad networks, you are engaged in criminal activity. Not because you fake viewing ads. But because you extracted a profit of this activity which was extracted from another party (via deceits).

Isn't the nuance mostly or only the fraudulently obtained debit cards?

I suspect the case hinged on that, and everything else was legal, albeit part of the fraud, and was included as a complete description of the scheme.

To be fair, I'm guessing he couldn't have created the scale of fake accounts without debit card fraud, but creating multiple accounts, even if they're fake, is usually just a TOS violation, or maybe a civil matter, not criminal.