Or maybe Meta’s walled garden is impenetrable to scraping?

afaik, that's the case for Instagram. After scouring the internet for frontends, there are 3 archetypes:

• black boxes like imginn, gets you images and nothing else. no source code to audit, self-host, or build an API
• self-hostable frontends that get rate limited almost instantly, even for a single user
• proper alternative clients that got cease-and-desisted into the ground

They did a great job making a panopticon, closed to the outside, yet devoid of privacy