My main issue with his "but discoverability!" argument is that the kinds of indie devs who would benefit from that discoverability are not the ones who will be getting these fancy deals from Epic Games. Vlambeer, Supergiant, Thatgamecompany, etc aren't 'up-and-coming' indie developers, they're well-established names who have had previous successes due to help from massive companies. In terms of indie developers they're the lucky ones, and the 'unlucky' ones don't have the name appeal or prior library to ever get a chance of being money-hatted by Epic.
Essentially I see the "Epic Games Store" solution to this problem to be a relatively selfish one instead of one that actually aims to help the 'next generation' of indies. You're going from "indie games fail due to not having good curation on Steam," to "indie games fail due to not having enough clout to get on EGS," and, overall, nothing really changes.