The young Reds full-back was criticised heavily on social media after his performance against Lincoln City in the Carabao Cup back in September.
Although Lallana insists Williams will become stronger after coming through the ordeal, he believes “keyboard warriors" are now part of the world we live in.
“I came across it on my own socials that he took a bit of stick," the 32-year-old told the Between The Lines podcast. “It was such ridiculous scrutiny and opinions from these keyboard warriors.
“This is a young lad that is learning. Of course, you're going to have some bad moments in games.
“To see a young lad coming through at a top level for a top team having to feel like he has deactivate or whatever, it's just sad, isn't it?
“You can have one average game and then all the keyboard warriors are out. He is a young boy still, so he is not going to be used to reading things like that.
"This is the world we live in nowadays. He's a good lad and I'm sure he'll be stronger for it, but it's not something that's needed with all the other pressures around."