It's criticized because it's useless for this use case, people involved in this scene in practice don't care about it to any serious degree beyond it being a talking point, and because anything for legally working around financial deplatforming still needs strong interfacing with the rest of the system as well as compliance with legal regimes, which BTC has nothing to say on that.
In fact, you can make your own payments platform denominated in USD and that's as useful as BTC for legal activities. So why go through the extra steps?