Riker and Ordershook formalized the voting calculus as:
pb + d > c
p = probability of vote ‘mattering’
b = size of the benefit
d = sense of duty
c = cost of voting
They argued that if pb + d exceeds c, people will vote. Otherwise not.
One can generalize this simple formalization for all political action.
A fair bit of technology has been invented to reduce c — it is easier than ever to follow the news, to contact your representative, etc. However, for a particular set of issues, if you reduce c for everyone, you are also reducing p. For as more people get involved, less does the voice of any single person matter. (There are still some conditionalities that I am eliding over — for instance, reduction in c may matter more for people who are poorer etc. and may have an asymmetric impact.)
Technologies invented to exploit synergy, however, do not suffer the same issues. Think Wikipedia, etc.