My best guess as to Russian interest is that by performing the sabotage in a difficult-to-attribute manner it plants the seeds for anti-US (and by extent, anti-Ukraine) sentiment in the public perception in the EU. More or less the governments of EU countries need the will of the people to back military aid to Ukraine, so giving the public something to latch on to from an anti-US perspective is valuable in that it could lower or prevent aid.
The Russians can also probably be secure in knowing that NATO won't publicly identify Russia as responsible as that would probably mean war and it has been very clear that NATO's top priority is avoiding the spread of the war in Ukraine.
There are some other possible Russian motivations I've seen, but put less stock in like capability demonstration and limiting incentives for a coup.
I'm not an expert, but my reading of the IRS's FAQ [1] is that the cost basis of inherited assets gets reset to the fair market value of the assets on the date of death.
Far beyond the value of TSMC, Taiwan is the lynchpin of the first island chain [1]. Taiwan remaining friendly to US interests is crucial to the integrity of the first island chain and thus the US island chain strategy[2]. In the event of conflict with China, control of the first island chain would allow the US to effectively interdict all maritime trade to China by denying access through the chokepoints created by the first island chain. This is frankly much more valuable to the US from a strategic perspective than TSMC (though TSMC is obviously very important).
You can also note the importance that Chinese planners place on this as well by looking at the Belt and Road Initiative, in particular the land-based projects that aim to connect China to European markets via rail [3][4].
The Russians can also probably be secure in knowing that NATO won't publicly identify Russia as responsible as that would probably mean war and it has been very clear that NATO's top priority is avoiding the spread of the war in Ukraine.
There are some other possible Russian motivations I've seen, but put less stock in like capability demonstration and limiting incentives for a coup.