/r/conservative is an odd example because I'm pretty sure everyone knows that the subreddit would be completely overrun by left-wing voices if they didn't enforce guardrails on this. At some point when tribal hatred becomes become sufficiently hot and lopsided in power, then the minority has no choice but to either leave or establish echo chambers. That describes the /r/conservative case imo.
In any case, I'm fully open to the idea that there are still right-wing echo chambers on Reddit. But the whataboutism is a weak distraction. The number of neutral spaces where people are allowed to effectively and openly disagree on hot-button policy issues has declined precipitously since the mid-2010s. Prominent powermods openly dictate what sort of opinions are "allowed" on various issues, and of course these boundaries are far to the left of the actual Overton Window of the populations whose democratic processes actually create policies.
In any case, I'm fully open to the idea that there are still right-wing echo chambers on Reddit. But the whataboutism is a weak distraction. The number of neutral spaces where people are allowed to effectively and openly disagree on hot-button policy issues has declined precipitously since the mid-2010s. Prominent powermods openly dictate what sort of opinions are "allowed" on various issues, and of course these boundaries are far to the left of the actual Overton Window of the populations whose democratic processes actually create policies.