Plausible deniability/difficulty of conviction means that LEOs rarely pursue cases where that would apply. I agree once they open an investigation, they'll verify the claim; I'm saying that crimes that have high acquittal rates and/or low prosecutorial uptake will get less attention from the police because it's frustrating/difficult/wasteful to spend a lot of time on things that don't usually pan out.

I don't know how the system works in Belarus so I understand it may not really matter there. The point is that it's going to be difficult to prove that the accused made an intentional connection to Tor as long as the accused and/or his/her lawyer has some technical literacy and knows what to say.

Not exactly; there's a lot of instances where something is 'decriminalised', that is, it's technically banned but you won't be prosecuted for it. (e.g. weed in the Netherlands)