I don't think they are goingt destroy Qward If AM is there.
Nor are they going to destroy Daxam unless they turn their sun back to red. DD can beat up DS but he doesn't have his powers.
Thanos can generate a planet wide omin directional blast, but this being who is limited to physical attack is a kryptonian who is arguably stronger than superman and can punch the planet into smitherines.
Like Bran said: DD=physical attacks only. Thanos=physical attacks AND extremely potent energy blasts. ie. Thanos can destroy a city's populace with a casual flick of his wrist. DD has to destroy a city's populace by punching each person one at a time. In the end you have the same outcome- but Thanos can reach that outcome MUCH faster.
As for the planets: they can only destroy Qward if AM is not present. Sakaar isn't an issue. They can only destroy Daxam if it's inhabitants are not under a yellow sun.