No-one likes to see the loss of any species. But I can never see the point of the talk of doom based on the notion that there are too many people in the world. China
does have a population restricting policy which has been eased in recent years as the consequential problems have become clearer. So what other solution is there to there being too many folks? Shoot them? That's been tried too but is not recommended. Increasing population is a fact that we have to live with, not something we can do much about.
But despite the railing against modern economies, it's the very success of those economies that (given population growth) provides the best protection for the environment
and has the strongest dampening effect on population growth; only the weathy with guaranteed pensions can afford fewer children
and have the time and cash to consider the fate of the planet's other species.
For example, the management of fisheries is increasingly subject to international protocols but the impetus for it comes from environmental movements in wealthy nations. Prior to the introduction
and policing of quotas, it was common for fisheries to be fished until they were entirely depleted - despite the fishing
The problem for the Malthus theory was that it looked at only one side of the ledger. That is, it saw food
production as static, when of course it grows in response to demand. One example relating directly to the OP's post is the development of fish farms. They are everywhere off our coasts and more will follow; the same trend that saw wild game
largely replaced by farmed stock.
That 'filling the void' is a core
principle of the practice of evolution; new species are evolving constantly to fill newly created voids. Evolution is not something that happened a long time ago; it's happening now and there is lots about it in the science literature. Here's a recent favourite. Birdfeeders Found to Cause Evolution of New Species : TreeHugger