It's a little bit more complex than that (IMO).
If you're doing something like high profile political assassinations and terrorism - you can expect the regime to expend "infinite" (from your perspective) resources to try to find you - and in this context, computers are incredibly bad at keeping secrets - bad enough that you should not use them at all.
But, if you're going to fedpost online about doing high profile political assassinations and terrorism, MANY things are going to be good enough - because without hard evidence that you're Actually Gunna Doo It, expending "infinite" resources to unmask you is just a neat way for the regime to waste infinite resources... And without the will to expend infinite resources, the whole "computers are incredibly bad at keeping secrets" thing doesn't necessarily apply.
However, I concur with Matty in that most major VPN companies are basically intelligence honeypots, so basically what they enable is low-level criminal shit that isn't worth it for them to blow their cover just to bust you...
