In election campaigns attention returns to broadcasting standards. Stopwatches re-emerge to count the airtime the rival parties and candidates receive. A thorough rethink of these mostly pointless rituals is overdue, especially as pressure grows for legislative action to tackle the harms to democratic processes for which social media giants are blamed, though they are not wholly responsible.

Lawmakers tend to build new sector-specific regulation on the old, adding to and tweaking a familiar model. But 20th-century broadcasting regulation is not fit for the purposes that regulation, co-regulation and/or self-regulation of communication must fulfil if notions such as an “informed electorate” are to survive.

Share-of-voice data misses a key element of campaigning: knowing when to be unavailable for comment

Share-of-voice data, as it is sometimes called, superficially offers a way to “measure” balance or impartiality in broadcasting. In practice this data cannot do so, and in some ways it misleads, for at least these reasons:

• To equate time speaking with benefit to the speaker neglects the subject matter and context. What was the audience actually hearing? Was the candidate delivering a campaign-wounding gaffe?

• Some political voices are effective through brevity, and others lack power despite length.

• Share-of-voice data misses a key element of campaigning: knowing when to be unavailable for comment. Parties may decline to contribute their voice on topics they find awkward, or try to shelter novice candidates from media exposure. Their consequent absence from the share-of-voice data says nothing adverse about the broadcaster.

• Incumbents naturally tend to get more airtime, partly because they have been governing lately, and partly because they will be called on to comment on domestic and international events during the campaign.

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Broadcasting laws date from a time when scarcity of spectrum justified licensing and content regulation, both of which the press struggled against during preceding centuries and escaped. Rules for radio and TV mostly predate today’s media, which digital technologies have blended. For example, newspapers pod- and video-cast, and TV networks curate text on websites. Broadly speaking, the online environment has been treated differently by legislators because it was thought that scarcity had given way to abundance. But it is clear now that a familiar regulatory challenge endures: sheer, distorting scale. This time it is not barons permitted to concentrate and deploy the power of media megaphones that reach mass audiences. It is corporations permitted to accumulate and manage the platforms and data that a mass of participants use and generate as they socialise. Not scale, massed and in the open; instead it is scale, atomised and to a large extent operating in the dark. Not Beaverbrook, but Facebook.

In social media during election campaigns, political players operate as individuals, as parties, through proxies (overt and covert), and as precision advertisers armed with unknown quantities of highly specific personal data about voters. The past always teaches something, but on the whole, broadcasting regulation as we have known it seems to have very little to contribute to a widely shared and pressing problem: how to create a framework that ensures that both free and fair elections and freedom of expression thrive in our strange new communications environment.

• Paul Chadwick is the Guardian’s readers’ editor