With PCs it’s one person per monitor. More can look on but it doesn’t work very well, and the content (software) is clearly for a single operator. Spreadsheets are not for performing.
With TVs it’s plenty of people per monitor. Like in a bar with sports on, or a living room with a family watching together. The content isn’t interactive, but then again interactivity is a concept defined by loner devices like PCs. Sharing a TV makes it a complement to direct interaction, like when everybody cheers a goal together.
Yes content on TV is one to many. But at least many are able to use the same device at one time.
A TV set is a social monitor. A computer monitor is a loner TV.