I believe it would not be advertising to display the next episode of a series, or even auto play it. But it would be advertising to display a different series or film.
For a fuzzier one, how about a newspaper providing links to their other stories at the bottom of an article that you have read? Typically I gain nothing by ingesting more of a particular publication's writing, so that could be an ad rather than useful functionality. Perhaps not in a special circumstance such as if I am trying to catch up on news local to that publication.
I don't really mind links to other articles at the bottom of the article that I'm reading. I mean, yes, it's a kind of advertising, but it's not intrinsically intrusive. If a site brings up a modal popup while I'm scrolling an article saying "OMG ENTER YOUR EMAIL HERE TO GET NOTIFIED WHENEVER WE WRITE ANYTHING ABOUT ANYTHING [or click this tiny text that says "no" in the most passive-aggressive phrasing we could think of]", that's a different issue.
(I kind of wonder if internet advertising would be a lot less hated if it had developed with a culture of restraint rather than maximum in-your-faceness, although to be fair, I'm not sure how that could ever have happened.)
I believe it would not be advertising to display the next episode of a series, or even auto play it. But it would be advertising to display a different series or film.
For a fuzzier one, how about a newspaper providing links to their other stories at the bottom of an article that you have read? Typically I gain nothing by ingesting more of a particular publication's writing, so that could be an ad rather than useful functionality. Perhaps not in a special circumstance such as if I am trying to catch up on news local to that publication.