I'd argue that the emergence of capitalists and capitalist ideology, and the amassing of currency is just a natural tendency of currency itself. Currency itself is a tool of transactional thought, and I'd argue that if we could move away from transactional trade and focused more on mutual wellbeing, we could do without currency entirely.

But without checks and balances then we could end up with corrupt plutocrats like the Soviets had.

The heart of Marxism is spreading power out as much as possible by giving the working class control over our resources and economy.

Howso? Capitalism is when non-worker investors own the means of production. In a co-op the workers literally own the means of production, so the workers are getting their fair share of the profit.

Sorry, but your comment is based on vibes and not on evidence.

But they also had catastrophic failures in food provision

Not the case. The famines suffered in the USSR were preindustrial, and a consequence of difficulties during collectivisation together with bad crops. After the industrialisation of the country, hunger was abolished.

And large, centralized economies are vulnerable to seizure by centralized power structures, who then turn them to their own ends

You're conflating centralisation with bureaucracy. There's such thing as democratic centralism, and it's arguably as resilient to corruption as decentralised competing structures.

But even ignoring those issues, a lot of this is just the same argument apologists for capitalism use. "Life got better and it was all thanks to our ideology!" A lot of this is conflated with general technological progress and other social changes, and the fact that human welfare was shockingly low in the economies that preceded modern ones.

You're saying all of that as if the industrial development in these areas is something independent of the ideology. Latin America and the Russian Empire in 1917 were in very similar stages of development. By 1970, the USSR was the second world power and brought immense welfare state while Latin america was left underdeveloped and exploited. Eastern Europe would most likely be on the level of development (and capital participation by western countries) of Latin America if it weren't for actually-existing socialism. The only other countries that managed to industrialise meaningfully since the early 20th century have been Japan and South Korea by being geostrategic US allies that directed immense aid towards industrialisation (a possibility not all countries, especially not socialist ones, have the luxury of); and China, first through planned economy and after the Sino-Soviet split again through opening the floodgates to western capital mixed with central decision-making. Technology doesn't improve everyone's lives, go to Guatemala or to Peru, or go ask immigrant workers in Saudi Arabia, or farmers in Sri Lanka. It's precisely socialism that allows everyone to enjoy these benefits.

Looking at history I don't see much difference. Both systems centralized wealth and goods into fewer hands

Laughably false. You say "looking at history" but you patently haven't researched any serious economic analysis of inequality in AES countries.

at the expensive of those that lacked political power, often with horrific consequences.

Then please explain to me whether there was a marked reduction in income disparity between farmers and white collar workers in the Soviet Union after the 1950s. I'll look for the numbers in a second (a good source is Albert Szymanski's "Human Rights in the Soviet Union"). Edit: found the numbers:

Both destroyed the environment as they industrialized, and continue to do so

Both don't continue to do so because most AES countries are gone, but you're right, we need to have a model of countries with high human development and sustainable carbon footprints... as is the case of Cuba, the only country in the world to my knowledge with both high HDI and sustainable carbon footprint. Concerns for the climate and for ecology are very much a 21st century thing, and it's to be expected that a power such as the USSR which was in a constant struggle for survival, didn't prioritize that. We can and should do better in the future.

Seriously, you are showing a clear lack of knowledge in the material and social conditions in actually existing socialist countries, and you should reconsider how much of what you know about them is factual and how much is a consequence of the power structures in your particular country telling you that.

Seems to be that while trade was helpful in the past, it is now an obsolete practice that creates power imbalances and should be abolished as a practice entirely.

The tagline they have on trade-free.org is:

"the ones who offer, should not ask anything in return

the ones who receive, should not have to give anything in return"

they are very efficient ways to aggregate information and make collective decisions without any top-down decision-maker

Macroeconomic decisions are made by certain people who in most cases belong to a specific class to favour the interests of the market, so there is no such idea of "making collective decisions", collective for the market is only the class it serves and we know which class it is