I think the word "accelerationist" has the potential to become the next "tankie", or even a worse, more mainstream version of it. In the way a small number of liberals are currently using it, it is equally useless for understanding the world / equally useful for misunderstanding the world. It can be used to equate any leftist with a person who wants to start WW3. It can be used to draw a connection between the far right and the far left, without even having to use another concept like "authoritarianism" to mediate the comparison.
We are also quickly approaching the part of the American electoral cycle where liberals will start trying to suppress any non-abstract criticism of the Democrats. "Bernie bro" will start to seem outdated, so they are in need of a new rhetorical tool.
"Tankie" could also serve as this tool, but it has the downsides of its meaning being harder to intuit from the word itself, and its explanation including an actual historical event. "Accelerationist" is also directly rhetorically related to the current campaign of hate towards LGBT people, but does not necessarily reference it so it can still be used by cis people to insult trans leftists.
Also, the western left just isn't at a point were accelarationism makes any sense strategically. In about any imperial core country, better organization and mobilization means it's fascism that would be much more likely to benefit from a systemic collapse.