Ashley Young (38) was sent off, while Everton were left aggrieved by Ibrahima Konate (24) avoiding a second yellow and also VAR granting Liverpool a penalty, converted by Mohamed Salah (31).
"It's a tough day. It's always going to be tough to come to Anfield as an Everton player," Pickford said after the full-time whistle.
"We gave it our all, worked hard and decisions definitely didn't go our way, no shock there.
"I think the work-rate we've put in was second to none after going down to ten men.
"After about half an hour, we dug in and they created chances - like they were always going to. We put up a good fight. As a team, we're not far off.
"Coming here is always a tough place, but we had a right good go and were always in the game - even with ten men. Going down to ten and the lads putting a shift in, you're going to get tired."
Asked if he believed Everton were on the wrong side of the officiating, Pickford told Premier League Productions: "It's not rocket science to work it out, I think the whole world will know.
"We can't comment too much because you will just get done anyway. A bit of dialogue would be nice and less arrogance would be nice as well."
