I guess the one angle I can see is that by watching the local copy, you aren't seeing any ads that might be on the page/video. But the website could embed ads into the downloaded video.
Really, how is this any different than recording TV on a VCR (or DVR)?
Each time a viewer watches a video a monetised channel makes a little more money. This money either comes from ads or Youtube Premium fees (Premium viewers are worth significantly more than free viewers).
Programs like yl-dlp bypass this - non-premium users can download ad-free videos contributing a single view to a video and consume that content any number of times. Youtube no longer makes advertising revenue per view, and content creators no long get their cut.
None of this is the case in TV, where ad revenue must be based on metrics other than straight-up view count, which cannot be counted meaningfully.
> But the website could embed ads into the downloaded video.
Many video creators do embed their own ads, but revenue from these ads are often based on view counts maintained by Youtube as well.
Why should they get a cut every time I view a video? If I watch a video saved to disk I use 0% of YouTube's infrastructure and cost the creator 0% in extra expenses.
Do I owe them a cut if I remember part of a video? Do I owe them a double amount of ad watching if I watch the video with someone else? Do they owe me a cut if they repeated a detail from a Wikipedia article I edited or web page I wrote? What about their college history professor that taught them a historical fact, do they need to go back and pay them when they reference it in their video?
For any bit of created media there are hundreds of uncredited and uncompensated second order contributions. The idea that someone making a YouTube video should get compensated every time I watch it is absolutely absurd. They're certainly not tracking down every second order contribution to the video and compensating them in turn.
If you buy a CD you pay for it one time. The artist doesn't get a nickel every time you play a track. You could put it on repeat for 50 years and they'll never get more than your up front payment. The only entity being paid is your power company for running that CD player for 50 years. If you powered the CD player with a solar panel and battery would you feel the utility company needs to be paid for your use of electricity despite not using any of their infrastructure?
You don't send a plumber a check every time you flush your toilet. If I watch a YouTube video once it's simply ludicrous to suggest I need to pay for a second viewing if I'm not using anyone's infrastructure but my own.
It really isn't. Except that we don't have easy-to-use DVRs for internet TV the way we used to have easy-to-use VCRs/DVRs for broadcast and cable TV.