I don't download apps if the place has a website. I don't want some garbage company on my phone unless it's in a browser. Infact most applications are just trash and show limited functionality of the website, nothing more. Most program d are literally useless trash.
You need it to share URLs. You can't know the device it will be opened on. Also, news articles sometimes embed them, which they use to hoard information about readers.
I was really hoping this would say “why does Facebook and Instagram provide a web interface when their crappy platforms rarely show content unless you’re using their app”.
At this point it’s purely a performance that they even offer a web interface to their platform.