We live in a post information scarcity society and we still haven't moved on from capitalism.
Edit: Changed title to be more accurate.
Also here is the summary from Wikipedia on what Post-scarcity means:
Post-scarcity is a theoretical economic situation in which most goods can be produced in great abundance with minimal human labor needed, so that they become available to all very cheaply or even freely. Post-scarcity does not mean that scarcity has been eliminated for all goods and services but that all people can easily have their basic survival needs met along with some significant proportion of their desires for goods and services. Writers on the topic often emphasize that some commodities will remain scarce in a post-scarcity society.
Capitalism will collapse eventually, whether planned or not. The best we can do is build up parallel structures that can weather that collapse, like complex networks of Mutual Aid, strong Unions, FOSS software, and more.
Fascism is similarly unsustainable, if we fail and can't achieve Socialism from Capitalism then fascism will take its place, and will also collapse. Same with climate, if we fail to properly handle it we will almost certainly go extinct, but the door remains open for life in millenia.
Even Socialism seems transitory to me. Much better than Capitalism, but once labor can be more broadly automated, we need to think of something other than money quickly.
Everything is unsustainable. So far, nothing has been observed to last forever.
Fascism tends to collapse a lot faster than capitalism though, because of its inherent drive to rework the world into something new. Fascism cannot abide non-fascism existing, and contains the implicit imperative to invade and impose fascism.