I'm also largely skeptical of the claim that Google is going to completely drop the ball here, but this is classic Innovator's Dilemma - sometimes a business can't effectively segment their existing customers enough to introduce a higher initial cost but ultimately better technology.
I think a Google Search Premium that cost $50/month would go over pretty poorly with Google's existing customer base (advertisers), but a startup can experiment with the business model with the right early adopters (e.g. Neeva).