Buying new ultra-low-performance hardware makes no sense even in that scenario. PCs can last decades. People in the US would just hoard used components. And piracy still exists even though there was real effort to end it. So I guess the jailbreaking/right-to-repair community would eventually get around the limitations.
There are plenty of examples where the absolutely strictest regimes tried to restrict their citizens' access to foreign goods. And black markets always won.

The firearm situation is a bit exceptional though. Being armed might make resistance a bit more viable once a large percentage of the population stops fighting each other over whether futanari are men or women.