The scraping wouldn’t be a problem if Reddit simply provided an RSS feed or other data-efficient API
Reddit does provide RSS feeds, e.g.: https://www.reddit.com/r/SonicTheHedgehog/.rss
Frankly, I'm surprised they still offer RSS feeds. They've been slowly but surely killing off all ways of accessing their content for years. One day they'll disable them, but for now they still work.
The "scraping" part becomes unethical when the scraping is so aggressive that it takes down the website (or severely impacts its ability to serve actual clients).
Archive.org scrapes the web all the time, but it doesn't do it so aggressively that it becomes an issue for the websites they're scraping. The same cannot be said for AI scrapers.