A simpler explanation is that they haven't really been collecting much in the way of tariffs yet.

Incidentally, my Nostradamus hat says: the US dollar weakness is going to bounce, for a short while, then resume.

I think that part of the reason for the slide was the huge pile of stuff that everybody under the sun tried to cram into the US before the tariffs kick in (dollar weakness). At some point they WILL kick in, and this will lead to a rebound period of unusually low US imports (dollar bounce) while the backlog of in-country inventory is sold off. When the steady state is reached (imports matching sales) then the textbooks say that a tariff country will see its currency rise, other things being equal.

Offsetting that, and confusingly in the other direction--a long term weakening tendency. To overgeneralize, if non-US investors don't put $1.1 trillion in NEW incremental investments per year into US stocks and bonds (and perhaps some factories), the dollar will fall. Those non-US investors with US portfolios don't have to sell anything for the dollar to fall, they don't even have to stop buying incremental investments, they merely have to buy incremental investments at a slower rate. I think enough non-US investors are, like me, now a bit leery at the margin for this number to average a much lower level in the years to come. This would be expected to lead to lower average valuation levels for US stocks and bonds, as well.

It's a mug's game to guess which of those longer term factors will prevail, but my gut feel is the last one. So, talking head prediction: a bounce, followed by a longer term jagged weakening trend.
USD index at 99.44 at the moment. Around the lowest since mid 2022.

Jim