If a definition can be changed in a way that makes it both simpler and removes an edge case, I think that is often (but not always) a sign that the change may be a good one.

(Though, that doesn’t imply that the best available definition won’t have any edge cases like this.)

I think it works better to define whether or not something is advertising based on, rather than whether the viewer wants to see it, instead by whether those putting the media where it is intend for viewing it to be (as far as they can make it) a requirement for something else.

Though, I’m not sure that even that should be considered a requirement. It seems to me like the things businesses paid money to get put on the million dollar website, should count as “ads”. I don’t see why we should define “ads” to refer exclusively to objectionable ads.

Definitions aren't that important. What's important is figuring out what contributes to society and what ends up just looting our attention.

A good (but not perfect) guideline is that voluntary transactions are beneficial to both parties because otherwise they wouldn't participate, and transactions where one party doesn't actively agree to it are often bad because the other party has no incentive to make it otherwise.

That's why I focused on whether the viewer actually wants it. If I seek it out, then it's useful or at least entertaining. If I don't, then it's probably a net negative for me.