I'd phrase it as "DDG claim they unwilling to rob their customers as much as industry norms to be able to afford the fee" (a fee they're paying to who?) to be on the list.
Customers are not consulted at any point. Customers are largely unaware of what Google have done to them via surveillance. Customers never agreed in any meaningful way to what google have done with their massively succesful surviellance bait and switch strategy.
Controlling the sales infrastructure and selling in that infrastructure is a thing that would be exceedingly difficult for it not to be anti-competitive.
It's been a problem in this industry at least since Microsoft were known as the death star and anyone successful in software found out they had just done microsoft's market reseach for them. Maybe longer?
Doesn't matter how long, it's gotta go. Beyond a small size you do distribution and nothing else or you use that distrubution to get sales. You got big? Splin off one of those parts and sell it while counting the money from your immense success. There's no way the current system is better for anyone other than those that want market power rather than producing high quality stuff.