She seemingly never considered that a system established through violence would later be upheld through violence.
She... kinda did. That's, like, one of the most basic principles of Marxism. Hell, Engels was the one that wrote it down. Just because one allows political dissent doesn't mean that they wouldn't use violence against threats to the socialist mode of production. Just because Luxemburg didn't favor democratic centralism didn't mean she was opposed to the use of force (which is a prerequisite for any especially revolutionary government seeking to uphold any ideology). That
is rather ironic given that she was killed by a revolutionary government upholding an ideology, but that's how history works sometimes.
So Rosa Luxembourg, former Soviet Embassador to Mongolia, is finally free to publish her tell-all memoirs and theoretical takes in the post-Stalin thaw of the ‘50s and ‘60s?
I mean, if Gulag Archipelago of all things was allowed, then sure. Joking aside, she'd probably find someway to publish them during and after de-Stalinization, and if not then, then someone down the line (maybe her kids if she has any ITTL) would publish them during the Gorbachev and post-Soviet eras.