First off, I'd like to welcome msszczep to the community!
msszczep has written a couple of thoughtful posts about unifying the Left, here and here. Both very thoughtful posts, you should go read them.
I do however, think that msszczep's idea of emphasizing reduction in markets is substituting one course of action for another. Their preferred course of action is on the same rhetorical 'level' as an emphasis on Voting Rights. It's not that it's incorrect because some other course of action is better, it's incorrect that it's not broad enough. It's exclusionary. Only the people who come to the Left because of voting issues will be enthused. But let's take a closer look as to why.