Found this interesting:
https://torrentfreak.com/sky-subscribers-piracy-habits-directly-help-premier-league-block-illegal-streams-210828/UK ISP Sky Broadband is monitoring the IP addresses of servers suspected of streaming pirated content to subscribers and supplying that data to an anti-piracy company working with the Premier League. That inside knowledge is then processed and used to create blocklists used by the country's leading ISPs, to prevent subscribers from watching pirated events.
Seeing as Sky is the broadcaster of the Premier League, it makes sense that they are actively seeking to block anyone else illegally streaming the Premier League.