I think it’s a shame that his ideas had carried a public taint to them for so long, due to several authoritarians co-opting his message

While we might point to some Socialist experiments that succumbed to needless authoritarianism (for example, Romania), This is a view that looks at 20th century socialism, and collapses the experiences of these places. Just the former eastern bloc, for instance, is far more diverse, socially, and politically, than westerners often caricature it as.

The aforementioned example of Romania, with its horrific treatment of women, vs the comparatively very modern East Germany with its state-owned gay bars are in many respects, world apart. Collapsing these places with a blanket term of "authoritarian" and waving it away as all just an unfortunate shame, is unhelpful at best, and actively anti-intellectual at worst.