“Dear children, this is the last hour; and as you have heard that the antichrist is coming, even now many antichrists have come. This is how we know it is the last hour.”—1 John 2:18
The man to whom Jesus gave the Revelation to wrote this in one of his other inspired letters. Paul elsewhere refers to the “man of sin” (lawlessness) who waits to be revealed (2 Thes. 2:3).
“Dear children, this is the last hour; and as you have heard that the antichrist is coming, even now many antichrists have come. This is how we know it is the last hour.”—1 John 2:18
Note, he said “last hour” twice in the same sentence, and whatever your conception of “anti-christ” is, the time for the appearance of the anti-christs was upon them, not thousands of years in the future.
And if you read the next verse, it identifies the anti-christs as coming out of the church, not some exalted government entity. That is one of the reasons that Peter (I Peter 4:17) said judgement must begin at the house of God.
James 5;8 “...for the coming of the Lord draws near,” the “last hour,” referred to by John.
When I was a teenage, I could not read the New Testament with any comfort for what I was taught because it was so obvious that All the writers of the New Testament, and Jesus, believed He would return during their day.