Political Memes

Not even close: political systems (governance of people & their actions) aren't economic system (goods & services), and authoritarianism is a political system.

Not even arguing about capitalism: left-wing authoritarianism is still everything I wrote regardless of capitalism. Those liberal democracies I mentioned still in principle limit authority of governments unlike those regimes whose shitty philosophies lack any such scruples: authoritarian philosophies authorize unlimited government power to repress universal rights & liberties. A non-exhaustive list of authorized abuses: the Soviets had their great purges; the Chinese communist party punishes generals for refusing to mass murder civilians, suppresses discussion of times they've sent tanks against civilians, persecutes the Uyghurs & Falun Gong, & represses the freedoms of its LGBT+ population to express themselves & form establishments on- & off-line to meet. These actions aren't backslides from their philosophy.

When liberal democratic governments commit human rights abuses, their philosophy at least recognizes them as illegitimate backslides from that philosophy, and on recovery the people may freely try to hold their governments accountable as they freely condemn such injustices.

However, let's appreciate the hypocrisy of your position. You're posting your criticism of capitalism on a online system created in the free world, and you're benefitting from the freedom to express yourself respected by your government, likely a liberal democracy with some form of mixed economy that includes capitalism. No government authority is shutting you down. We couldn't safely claim the same if you criticized your government's economic system from a state run by a left-wing authoritarian regime.

Even supposing capitalism is authoritarian in some way, it's not the government. Left-wing authoritarianism purports to fight oppression by becoming (causing and perpetuating) oppression. Left-wing authoritarians replace their economic elites with political elites only unlike before, these elites can now run wild with unrestricted government authority to terrorize the masses: they claim that's progress.