Vice article is wrong or at least unclear and Slashdot summary is worse.
I wasn't the executive goverment who issued the takedown order for the website, it was a judge. There is separation of powers in Spain, you know Goverment (Executive powers), Legistative (Parliament) and Judicial Authority (Poder Judicial in spanish). It isn't perfect, sure :-) , show me a country on Earth it is.
I don't know what did the app nor why it's been banned, but I'm sure protesters can use other means like Whatsapp or Telegram or Signal or whatever, or just use a VPN, so I don't think it will really make any sense.
Businesses have to comply the laws of the countries they operate on, so I don't see what else can do any company doing business in Spain.