I'd be interested to know what the rationale for the new design was. Some kind of dark patterns? Make people so disgusted with the web version they just download the native app, which provides better monitoring and "stickiness"? I mean, is anyone at Reddit actually proud of the redesign?
I assume a little of column A, little column B. Web devs who wanted a greenfield project and a PM willing to be convinced, because 1) old reddit still exists to fall back on and 2) in retrospect outcomes pushing users to mobile seemed to be good for monitoring and stickiness.
I blame typical tech dysfunctions and the interests of users not align with short term stakeholder interests.