Captured Russian Weapons Are Packed with U.S. Microchips
thedrive.com
thedrive.com
The war (and thus sanctions) has only been going on for a couple of months so I doubt it's due to sanctions, so if it is true then I'd expect it to be caused by the general chip shortage, however I also doubt it since I'd expect Russia to have a big enough weapons stockpile to not have burnt through all of it in the span of a few months as to need to scavenge components from household appliances to make more.
Probably shows that you want to make a thingee that blows up stuff, electronics and computing is not what matters the most.