Reduced world stability for sure. Their withdrawal from the world stage under trump (and I might say their abstinence from global responsibility (climate change being but 1 example, but also with respect to military rhetoric)), has in my opinion been one of the factors leading to the current state of affairs we find ourselves in. Of course the pandemic has also led to economic instability, but had it been handled domestically better, rather than downplaying it, and suggesting bleach IVs, the economic picture may have been more favourable elsewhere also, and dictators may have been less inclined to be so bold.
Of course there are lots and lots of factors at play here, but the irresponsible trump administration won't have helped.