Uncontrolled reentry has been the norm for most of the space age (and is still standard practice for the Chinese, and their boosters). The far more important issue is that this a human-rated booster, and an unidentified defect impacts the safety of crew launches. This issue showed up on a de-orbit burn, but it's unlikely to be limited in scope to de-orbits only.
edit: Turns out this isn't accurate; it's still actually normal for US rocket *upper stages* to do uncontrolled reentries [0]. This is a subject of ongoing FAA rulemaking [1]. The Chinese examples are still exceptional because they involve far larger first-stage/core-stage boosters (>50 meters in length).
edit 2: If anyone was curious about the Europeans, the answer is that Ariane 5/ECA has actually *never* done a controlled upper-stage deorbit, because its LH2/LOX engine isn't designed to be able to ignite twice (deorbit burns are excluded)[2].
China also often launches from far-inland locations which puts large terrestrial populated regions beneath the booster (and booster landing) track. Perhaps less so for nominal launches, but not all launches are nominal:
China operates four launch facilities, three of which, Jiuquan, Taiyuan, and Xichang are inland. The fourth, Wenchang, is on the island of Hainan, in the South China Sea between China, Vietnam, and the Philippines.
Russia's Baikonur Cosmodrome, located in the independent country of Kazakhstan, is similarly an inland location and has seen launch debris fall over populated areas.
edit: Turns out this isn't accurate; it's still actually normal for US rocket *upper stages* to do uncontrolled reentries [0]. This is a subject of ongoing FAA rulemaking [1]. The Chinese examples are still exceptional because they involve far larger first-stage/core-stage boosters (>50 meters in length).
edit 2: If anyone was curious about the Europeans, the answer is that Ariane 5/ECA has actually *never* done a controlled upper-stage deorbit, because its LH2/LOX engine isn't designed to be able to ignite twice (deorbit burns are excluded)[2].
[0] https://outerspaceinstitute.ca/osisite/wp-content/uploads/OS... ("Uncontrolled reentries are currently used for 35% of U.S. missions (62% if we exclude SpaceX)") (as of 2023?)
[1] https://spacenews.com/new-upper-stage-disposal-rules-help-no...
[2] https://www.sciencedirect.com/science/article/abs/pii/S00945... ("it is not possible to perform a controlled reentry of the Upper Composite")