Having a debate with an Italian guy about who is the bigger club and I think it’s close.
Both have won their domestic league 19 times and Milan have 1 more Champions League.
Milan probably have more well known legends like Van Basten, Kaka, Maldini, Gullit and Pirlo. But in recent years Liverpool have had Gerrard, Suarez, Alonso, VVD and Salah.
The current popularity of the Premier League helps Liverpool but Milan also has a huge fanbase.
Numbers wise, I’d say Liverpool is the bigger club, but Milan has made it’s mark in football history more. The reason Liverpool has more fans is because it’s a big Premier League club, both with the Premier League being the biggest and because of the influence of English people in the world.