[dspillett]

They haven't evolved to stop issues happening, partly because many a consumer won't understand the need so won't accept it (I'm returning this because it never charges to 100%) and there isn't enough demand from elsewhere for it to affect sales of devices (in office environments those laptops are usually cycled out before it would be a significant issue anyway).

But these days there are often controls in place to cut off power if things look bad (battery getting too hot, mainly) so things are more likely to die on their own rather than setting fire to themselves and anything near-by.