It's similar to how I would expect my ISP to not block the websites of competing ISPs. That's forcing the ISP to have content move through its system that it may not like.
It's the same logic behind forcing private businesses to ban smoking on their premises, and the same logic behind forcing photographers, bakers and florists to provide artistic services to celebrations they abhor: 'if you don't want to do X for everyone, according to the rules and regulations we have promulgated, then don't do X!'
The sad thing is, most folks don't want liberty for others.
I certainly don't want unchecked liberty for others, or myself. I want intelligent, compassionate, and humane liberty, meaning that you can do whatever you want as long as you're not hurting someone else.
Say I take the grocery example from above. And I have unbridled liberty, and I now don't allow any black people to shop there because in the original texts of Mormon, the lord cursed Cains seed, and the black skin curse was to identify the cursed. Now if there are 30 grocery stores in town, who cares. But say I'm in a small town, and there are only two, and we're both Pre-1978 Mormon believers. Now black people in the town can only eat at the Chick fil a. Well, Chick fil a decides to also have this policy, and now there is no place for the black populace to eat. The only option to the black people is to open their own store, except no one will sell them the food, and no one will sell them the land, and no one will sell them... anything. I effectively own the black populous because I can get them to work for food. Oh, and it's not racism, it's religion.
I don't care what ideology you have, it must not suppress human rights.
Yes I do! If you don't want to host hate speech, don't go into the hosting business. Sell groceries or something.