I don’t have any data, but my intuition is that overall high-fee, high-reward cards increase propensity for consumer spending by at least a few % beyond the fees/rewards.
The merchants think so, too, or they wouldn’t accept the processors that let their banks hand out these cards.
Visa / Mastercard / American Express all have lines of premium credit cards (Visa Infinite, World Elite Mastercard, Amex Platinum), and they're very much too big to ban. You'd just be left with one processor in the US (Discover, now owned by Capital One).
If they’re truly too big to give up no matter the fees they charge, they’re leaving money on the table.
Of course, they can’t. If Chase started handing college students a 3% card, the merchants would riot.
In recent years, all of my utilities have added 3%+ credit card surcharges, so I pay most of my household expenses with debit cards/ACH now.
Tmobile, Comcast, Verizon, ATT, Target, grocery store, electric utility and water utility (government), annual vehicle tax (government), auto body shop, daycare, and any home repair contractors all charge 3%+ (or give a discount, same thing), so I basically only use credit cards for other retail stores and travel and restaurants.