I agree that it's worth acknowledging the effects of 401ks as having some downsides for retirement in general. That said, I don't think it's fair to consider it a "significant" downside at face value when the upside of the transaction is that you can leave it to your heirs. For someone who values individual agency and family values that's going to be an upside, for someone who values optimizing around what benefits society at large it's obviously a negative. I might also be wildly misunderstanding you though so please correct me if I've gone off track.