Explorer and ISS all took on catastrophic damage after encountering the first round of debris. Somehow the Chinese station took minimal damage after two rounds of debris? But then the third round completely annihilates the station right as Stone is escaping? How very convenient.
Other than that the movie is near flawless and I love the atmosphere.
Failure is yours in understanding the situation. You falsely assume that everything in space is getting hit at the same time.
The Debris cloud is not everywhere in orbit simultaneously.
The movie makes a few fictional presumptions. Namely that the ISS Hubble and Tiangong are all in the same orbit (though at different points in the orbit).
The Debris cloud is CROSSING the orbit shared by the three other locations.
The point at which it crosses the orbit is where it can strike things at that point.
Obviously when it hits one, it cannot be hitting the other. So your assumption that all three... Shuttle, ISS, and Tiangong, were getting hit all three times that we see the debris is an error on your part.
1ST STRIKE
Explorer/Hubble: take a direct catastrophic hit and are destroyed.
ISS: Being relatively nearby and at the edge of the debris field, suffers some damage as they did not receive a direct hit, ISS crew abandons station under orders leaving the damaged Soyuz behind.
Tiangong: Being even further away, is not struck by the debris at all. Crew abandons station after setting it to deorbit rather than remain to become a part of the growing chain reaction of debris, knowing it will get hit sooner or later if it remains in orbit.
2ND STRIKE
ISS: This pass, ISS takes a direct catastrophic hit and is destroyed.
Tiangong: In the process of slowly falling out of orbit again receives no hit but debris passes closer this time.
3RD STRIKE:
Tiangong: takes a damaging but non catastrophic hit just as she is starting to enter the atmosphere, most of the debris cloud is above the station in a higher orbit that the reentering station. Station is destroyed due to reentry into atmosphere.
I joined the Navy to see the world, only to discover the world is 2/3 water!
And why was there nobody on board the Chinese station when she got there?
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Answered already. They too had to abort and abandon station and perform an emergency return to Earth, Just as the ISS crew did and the Explorer crew at the Hubble was attempting to do when they got hit.
I joined the Navy to see the world, only to discover the world is 2/3 water!