Within maybe the last couple weeks, they also seemed to start blocking some Tor exit nodes.
I guess at least 50/50 it's an anti-abuse measure (rather than surveillance capitalism), at probably some human cost of denying reddit as a venue/channel to oppressed people.
Incidentally, if anyone is using Tor in ways that show up as significant abuse to Reddit, that's hurting Tor for those who need it for more legitimate purposes.