Yes, as long as (for example) you have a huge number of people desperate to claim one or more of a very small number of slots for papers in a few prestige journals then inevitably there must be either a cattle-call selection process, or blatant preference for existing insiders, or both. But things like the fancy journals' reluctance to acknowledge or care about errors in the papers they do publish really aren't at all a necessary consequence of a high submission ratio or of a rapid growth in submissions. In fact it's not even clear that they are a consequence of those pressures at all, let alone that they do anything to mitigate them. They're just things which serve the interests of insiders while in fact making the consequences of the Darwinian pressures worse.