This one wasn't captured by the main camera. It used the periscope camera (see the exif data). The periscope camera captures more light per time from distant objects than the main camera because focal length / f- number = effective diameter is larger. It also offers more pixels per angle, therefore it can make more stars per angle visible than the main camera. Google still chooses 16s per frame for the periscope camera because a shorter exposure time per frame would require more frames and more frames would lead to more read noise.
In order to cause no star trails with the periscope camera, the exposure time per frame can't be more than 4 seconds. But this would require 4 times as many frames for the same total exposure time. This leads to more read noise. It is theoretically possible to compensate the higher amount of read noise by choosing a longer total exposure time, but this would require a total exposure time of 4 to 16 minutes (it depends on how much read noise the sensor produces). Though, I think it would be still better, if Google chose a shorter exposure time per frame for the periscope camera, it could be also a compromise like 8s per frame and total exposure time of 6 minutes. It would be nice, if Google let us choose the exposure time per frame and the total exposure time and gave us the option to save single frame periscope dng files with 3rd party apps.
Alternatively, one can remove the star trails by downsampling.