I think "stealing" is the semantically/technically incorrect term that's used as a sort of justification for not compensating the creator of a work, who paid to create that work, even though that work is considered valuable to the person using/watching it.

Hmm - is there a good summary of this argument I could read? I torrented many years ago and it always felt like stealing and still does. Seems more or less equivalent to shoplifting to me from a moral standpoint, would be curious to read into this!

(I'm assuming this is not the "oh I actually pay and I just want to watch it on an unsupported device" argument)

If I shoplift a bag of Doritos, the shop has one fewer bag of Doritos.

If I pirate a show, it doesn't disappear from Disney's hard drives.

People use "steal" like that all the time. "You stole my idea." "He stole my look!" "She stole my song." Etc... So I don't really think that's a very good argument.

What's a good word for "obtaining digital content without paying for the right to possess said digital content"?

The shop doesn't care about the Doritos. The owner isn't going to eat them. The shops only care about getting paid by who takes the Doritos.