The dollar has been strengthening against everyone. It appears that Bidenomics is appealing from that perspective. There are benefits and costs to the US as a result. Your cheaper imports are our more competitively-priced exports, for instance.
But as your article says, there seems also to be an immediate negative response to the mini-budget that is specifically-focussed on the UK. I hope market actors are thinking like me, that they are sceptical of the economics, but that it's a move that she may get away with if the Russia war ends soon and we see a sharp recovery. That would stop the rot somewhat.
I still think that the UK's relatively low debt ratio will provide support and make the sale of gilts appealing; and I presume that the Bank of England will raise interest rates some.