For Helix I’m afraid the only way is to query streams for each game returned by
GET https://api.twitch.tv/helix/games/top
and sum the viewers. It is much harder to get an accurate value though 
For Helix I’m afraid the only way is to query streams for each game returned by
GET https://api.twitch.tv/helix/games/top
and sum the viewers. It is much harder to get an accurate value though