Ask HN: How do Russia sanctions affect large tech companies?

I was able to find a couple HN articles from a few small entrepreneurs about the effect of sanctions [1] [2].

Does anyone know how sanctions apply to large tech companies?

For example, is Microsoft legally required to block Russian users from being able to download Windows security updates from Microsoft? Seems like black hats will soon have a free-for-all on any and all Russian Windows machines if that's the case.

For that matter, what about the Internet itself? Are companies in sanctioning countries legally required to firewall IP addresses that geolocate to Russia? Are ISP's in sanctioning countries legally required to blackhole IP traffic coming to or from Russia? Are transatlantic or land-based fiber optics running from EU, Japan or the US to Russia legally required to be shut down or even physically severed?

How do the companies that own those fibers pay for the fibers' operational and capital costs, considering that money now can't flow into or out of Russia? Even if the fibers are legally allowed to operate, wouldn't there be a financial incentive to shut them off, because nobody's allowed to pay for them because of sanctions? Are governments using tax dollars to replace the lost revenue, to keep those fibers open and allow some semblance of freedom of speech (and/or Western propaganda) to reach Russia?

Do the sanctions destroy Russian users' ability to access DRM-protected products they've already bought? For example if you're in Russia and you bought X game on Steam pre-sanctions, is Steam legally required to say "Sorry, because of sanctions I can't let you connect to the DRM server" and the game's existing DRM checks then say "Sorry, since you can't connect to the DRM server you can't play the game"?

[1] https://news.ycombinator.com/item?id=30539958

[2] https://news.ycombinator.com/item?id=30505819