Well we can look at attempts at socialism and see that some failed, some were successful: https://factually.co/fact-checks/politics/successful-sociali...

But of course success is relative to some cultural values. We could just as well wonder about success and failure in implementation of any political system.

The most remarkable trait of humans is cognitive plasticity, so determining any natural tendency that would be more inate than acquired is just a game of pretending there are hypothetical humans living out of any cultural influence that would still exhibit predominent behavioral traits.

Competition is a social construct. There are people out there whose biggest concern is keeping focus on enjoying what they are, freeing their attention from the illusion of possession, avoiding any financial/material bounds they can and staying away of contingent hierarchical servitudes.

They are also many people who holds desires for both of these perspectives, or any interpolation/extrapolation that they can suggest.

Is there a way to accept but also limit greed that is reliable and durable?

Like a pragmatic meritocracy. We accept that there will be cheaters, and we won't catch or stop them all, but we have some hard limits. Do we care if you stop working so hard once you hit $1b? Maybe we'd even prefer that you did stop working (against societies interest!)?

This wouldn't even remotely resemble the communism bugaboo. It's basically saying, yes greed can be good, but at some point it gets ridiculous.