For several reasons, first is that it's not difficult to stock on these chips. They had 4 years to stock up and will probably have years of stash to spend even if all supplies stop right now. I.e. enough to reach their goals.
And then, the real reason why controls were not ramped up during Biden, is it would make those chips less cost competitive to foreign alternatives. Chinese alternatives have been emerging recently, especially wrt. TI and AD, and they couldn't care less about a bunch of Ukrainian activists making a lawsuit in the US, they will happily make it easier for suppliers worldwide to get chips with no strings attached, eroding US market share in this area.
Chances are, too, that this lawsuit will be thrown out of court because of shift of (presidential) political attitude towards Ukraine and Russia and will be viewed as an attempt to harm US companies and introduce burdens on sales of these chips.
Government will lobby against it, and courts will be less likely to go against it. Maybe they picked their jurisdiction cleverly, aiming for anti-Trump judges, but then they better reach a settlement because at appeals or supreme court this will be thrown out with high likelihood.