Personally I look at the game business as a sort of "innovator's hustle," where most of the effort is going towards the novelty aspects - even in the design. Traditional/historical games have lasted by remaining captivating for lifetimes, rather than 40 hours, so raising the bar for long-term retention is not an impossibility, provided that a way to market the design over an equally long time exists. But it's far more straightforward to push for marketing-immediate elements(graphics, storytelling, ad campaigns, etc.) and that's led to an industry characterized by budget escalation.
From this angle, F2P's profit engine is primarily running on the basis that more novel and more appealing games can be made via a change in the business model. If the innovation stagnates, so will the market for F2P. But the business model isn't directly at fault for that. Tactics like blind conversion of every existing type of video game into a F2P straitjacket are what make it a fad, one likely to recede to a more reasonable level over time, but not one that goes away entirely.