You hard drive isn't airtight, so it's likely to accelerate failure. On PCBs, it creates a sticky residue and increases dust buildup, increasing the likelihood of a short circuit (somewhat) and a fire (very marginally).
'Smoke-free' equipment is definitely a selling in the market for music studio electronics, since (some) musicians smoke a lot and old dirty gear tends to be noisy and crackly because all the pots, faders, connections and so on may have years' worth of residue built up. ProTip: most people (an cleaning solutions) use isopropyl alcohol, but like all solvents this damages finishes and can affect electrical conductivity. There's stuff called Deoxit which is not too expensive and preferred by a lot of people for high-end electronics maintenance.
'Smoke-free' equipment is definitely a selling in the market for music studio electronics, since (some) musicians smoke a lot and old dirty gear tends to be noisy and crackly because all the pots, faders, connections and so on may have years' worth of residue built up. ProTip: most people (an cleaning solutions) use isopropyl alcohol, but like all solvents this damages finishes and can affect electrical conductivity. There's stuff called Deoxit which is not too expensive and preferred by a lot of people for high-end electronics maintenance.