It could, and it might not happen or be noticed right away. Although it has a much higher resistance than copper, etc., carbon (soot) is a (poor) conductor. I have seen a few cases like this and they are very difficult to clean. Most of them had or developed problems. I usually take the computer (including power supply, monitor, etc.) completely apart, which may void warrantees, clean, and run extensive benchmarks and burn-in tests. The keyboard could die an early death from it. Printers and monitors are vulnerable. If you have insurance, suggest contacting your insurance company.
If you are running a computer shop, never, never agree to be paid by the insurance company. You will probably be letting yourself in for a lot paperwork, phone calls, squabbling, etc. and may not be paid for a long time, if at all. I usually charge upfront for the estimate on this kind of work. Larry