Almost all of the violence happened away from the students and no one was killed in the square itself. There were other incidents around the city done by workers who were armed with guns and took a joyride in an APC. There were multiple protests being done by multiple groups without unity in their demands. To even unify the students with as broad of a demand as democracy is disingenuous. They were fighting one another for access to loudspeakers.
The students broadly represented the class of people favored by the 70s economic liberalization reforms. The workers were on the bad end of the reforms and were largely calling for a return of earlier, Maoist policies. It would be more accurate to say the students were more or less calling for increased liberalization, i.e., capitalism.