Anything that can influence actions is by definition some kind of technology. Cars are a good example. Inside a car I can only perform activities like steering the wheel, Pressing the gas and break pedals, Shifting gears, Stopping at intersections when the traffic light is red, Changing lanes, Making turns, Etc. These are all activities that do not make much sense in other contexts so a car is a technology that influences and restricts what actions I can perform in exchange for traveling from one destination to another faster than I would have been able to on my own. Similarly with symbols but instead of performing a physical activity, Symbols allow people to perform "telepathy". By creating sequences of symbols and putting them together into words and sentences people are able to influence the mental state of others. Nations and civilizations have been built on nothing more than some words and sentences because, At the time, They had such a great influence on those that were exposed to them that they changed their behaviors and actions in order to continue recreating those symbolic sequences. Viewed this way, Symbols are actually much more dangerous than cars because, Unlike cars, Symbols can take on a life of their own and propagate at the expense of those that were exposed to those symbols without knowing what they were signing up for.
Seeing as the definitions of technology that I have found seem to mostly refer to machinery, Equipment and similar aspects, I don't quite see how a symbol is necessarily a technology. However, The two groups can overlap, Meaning symbols being used for technology or technology being used as a symbol.