Possibly you don't realize that statement from the cross was a fulfillment of Old Testament Scripture. Jesus was acting as intercessor and showing His purity of heart concerning fulfilling the mission for whence He came. I do not see any place in the Bible where God forgives without humility, repentance, propitiation, reconciliation of the person seeking. It isn't a universal broad-brush/blanket forgiveness for all of humanity that was granted by the work on the cross anymore than it was a broad-brush/blanket forgiveness He was seeking for those he was addressing while on the cross. Instead it is a free gift to those that turn from flesh to Jesus and receive Him. He is ever willing for the Father to forgive but He will not be a High Priest in a way that negates the cross. Truth couldn't get any more basic and foundational than that.
Isaiah 53:12 Therefore will I divide him [a portion] with the great, and he shall divide the spoil with the strong; because he hath poured out his soul unto death: and he was numbered with the transgressors; and he bare the sin of many, and made intercession for the transgressors.