Yes, you could take off in zero wind and fly off a cliff but it's quite boring. I wouldn't even bother hauling my paraglider up a cliff on a windless evening when the there are minimal thermals. Not without a lift. The risk profile is is quite debatable. But the general consensus is that paramotoring is safer. I see it simply carying other risks, like tangling your lines in the propeller, improperly operating the engine etc. Also the number of yearly fatalities is smaller, which doesn't actually say anything without total hours of flight. For paragliding I think most uncontrollable risk mainly revolves around weather.