I agree.
As I see it, they are "lost", until He finds them ( Matthew 18:1-14 )...
" For the Son of man is come to save that which was lost." ( Matthew 18:11 ).
But, perhaps there's another meaning to the word, "lost" that is not being considered when you think of the term...
"Lost" as in "wayward" ( Matthew 18:11-14, Luke 15:3-32 in the context of the 10 pieces of silver, the 100 sheep and the Prodigal son ), versus "lost" as in "them that perish" ( 1 Corinthians 1:18 ) and condemned to Hell ( John 17:12, 2 Corinthians 4:3-4 ).
Or, to put it another way, the distinction between "saved" and "lost" in the eternal sense, versus "lost" and "found" in the temporal sense.
Within the bounds of the love I see that Jesus has for the "little ones which believe in me" in verse 6 and all the rest of what is stated in this first part of Matthew 18, I clearly see how much the Lord loves His sheep...
Those that are given to Him by His Father ( John 6:37-39, John 6:64-65, John 17:2 ) and that He would give eternal life to.
It's a particular love for a particular people...
The "whosoever believeth" and put their trust in Him and Him alone.
In addition, I clearly see in John 10:26 that unless a person is one of Christ's sheep
to begin with, they will not believe on Him...
Unless on is "of God" in John 8:43-47, they will not believe His words.