Additionally, varying interpretations would say you shouldn't use the lights, elevators, etc, so modern living in any manner may be incompatible with orthodoxy.
Similarly, observant users may use artificial light, they just may not turn it on or off. So there are Sabbath lamps where the bulb remains lit but a shade can be lowered to block out the light.
Are these modern cheats to allow observant users to benefit from the convenience of technology while ignoring the tenets of their faith? I'm no reliogiologist, but if these are cheats, they are ancient ones, not modern ones. For example in past times, people would cook before the sabbath then leave the food on a warm hearth with insulation for later consumption.