How spruce react to being “topped” is particularly interesting.
Once the current trunk or “lead” is removed, hormonal signals are sent to the next rung of branches telling them a new lead is needed. Since a forest tree typically has to continue growing tall or risk being shaded and starved, the next in line branches head the call by curling upwards and actually developing into new lead trunks. Although beneficial for a forest tree staking claim to its small patch of sunshine; this hydra effect can be highly undesirable for urban tree owners. Steadily growing heavier at the base of the former trunk wound (which will never heal) these second generation trunks are prone to splitting off in heavy wind or snow.
In summary: As a last resort (a spruce beginning to encroach on utility lines for example), a spruce can be topped, but you’ll be left with a fairly high maintenance tree, since the new leads will have to be pruned off every 3-5 years to prevent the tree from becoming dangerous.