Maybe these were all planned.

I read it somewhere a while ago, BoE was taking actions to devalue GBP regardless of the Brexit. Brexit probably just increased the effects. Maybe that's what they wanted in the first place, hard to guess.

Devalued GBP creates stress on the USD on the other hand. I bet Trump hates that weak GBP but can't really speak his mind as he does with the Euro because England is closer to the US more than ever now especially after the Brexit voting.

In the end, sooner or later, all of those major currencies will be at parity. 1:1:1:1... like a dead hearbeat. Nobody wants their currency to be a store of value. (Except one )