If your only problem is that you want more resources available for yourself, I can see how you'd come to that conclusion, but you're wrong. It wouldn't solve the underlying problems, and in fact it would create a whole set of new ones. Modern civilization depends heavily on economies of scale, and your magic finger snap does nothing to change how resources are produced, distributed, or consumed.

You're also assuming that every human consumes resources at roughly the same rate. They don't. Not even close. A tiny fraction of humanity consumes vastly more resources than billions of other people. Your finger snap doesn't address that inequality at all. The same people and systems that concentrate resources now would simply have an even larger pool of resources to hoover up afterward. Then what? Snap your fingers again?

And follow the logic to its conclusion. If reducing humanity to 100 million "solves" problems because fewer people are consuming resources and competing for them, then 1 million should be even better. Five thousand better still. Ultimately, zero humans means zero poverty, zero war, zero homelessness, zero human carbon emissions, and zero human suffering. Problem solved!

Except obviously it isn't, because eliminating the people who experience a problem is not the same thing as solving the problem for those people.

We don't have billions of people living in poverty because there simply isn't enough stuff on Earth to go around. We have enormous disparities in who controls resources and who gets to consume them. Fantasizing about eliminating most of humanity while leaving that system completely intact makes you a stooge for the oligarchs.