Maybe they are... alternatively maybe they aren't and it's simply easier and faster to tell troops to chuck washing machines onto trucks rather than spend time dismantling them and learning how to identify the relevant parts and remove them without damage, not to mention Russia has a lot of spare fuel now.
I find the connection to acquiring electronic parta dubious. No one would transport washing machines on tanks when other transportation means exist. Plundering by badly disciplined troops looks much more likely.
There must be some interesting chips in washing machines these days.