I understand the criticism to be targeted at the "web3" idea, which is assumed to be about the infrastructure for decentralized applications. What is possible to implement is less relevant than what is likely to get implemented: here the clients (read: the app on the mobile) and their means of accessing the decentralized goodness matters. The argument as I understand it is: if access/usage to whatever decentralized goods is always mediated by the old centralized approach (you have to ask the server whether the transaction is valid) then you trust the operators of the servers and those folks have the option of making "everything" (access to those services/goods) faster & better. It is like the "last mile" problem where a company may well operate a global network but have no setup to act as ISP for end consumers, which is left to mediator. This is compatible with "web2" (https vpns etc) but the "web3" answer seems to be missing.

The problem is that benefits of well-thought out incentive systems evaporate when access is mediated. If every dapp comes with its own mobile client and app-specific servers to address this, there is nothing decentralized about it.