Comment by KeplerBoy
What happens when a unit is defective and not easily repairable, maybe because the PCB itself was already defective?
Do technicians salvage the high value components, like the CPLD in this case, off the board? That chip alone is probably worth 15$.
As other commenter says, spending human time to save a $15 chip is uneconomic. This only happens if they're especially expensive parts or (as during COVID) supply is short and you can't just buy some more.
(COVID shortages saw the opposite phenomenon in a few places: working consumer electronics being bought and stripped for a particular part critical to something else, then the rest thrown away!)
Remember that after you've hotgunned it off the board and cleaned the solder you have to re-ball BGA parts. Again, a process that's cheap in the original manufacturing line and very hard to do by hand. It also means the part has been through more thermal stress which will shorten its life. You don't want to have to rework a unit again if you put a recycled chip in it which fails.