Because the article is badly written.

It’s confusing money spend on X must equal time spent on X.

The total amount of money spend on video games has gone done but more money is now being spent on things like crypto currency. This is being claimed that it means that people are spending more time on crypto since they are spending more money there. It ignores other issues such as who is spending on what (its countries as a whole, not amlunt on average per user), gaming is more expensive, more games are being made as a live service and are flopping (Highguard anyone?), retro gaming is getting bigger (doesn’t cost a fortune), etc…