The universe is bigger than the part of it we can see. The part we can see is large enough that there statistically has to be life out there, but it's also so large that we'll never sense them let alone communicate with or see them.
The Antichrist is NOT a prophesied entity. There is no, "the Antichrist". Antichrist isn't even mentioned in the Book of Revelation.
Antichrist is only mentioned in the 1st and 2nd letters of John, where it refers to many antichrists (1 John 2:18), who are identifiable because they deny the Father and the Son (1 John 2:22), and that Jesus Christ has come in the flesh (2 John 1:7). The term simply means, 'against Christ', so anyone who is against Christ could be labelled such, even if they didn't match the description in 1st and 2nd John.
So antichrists existed when these letters of John were written and an innumerable number of them have existed over the past 2,000 years and exist even today. While antichrists would likely continue to exist while the events in Revelation occur, they are not described as having any role in the events described in Revelation.
The reason people link antichrist to the beast or false prophet in Revelation is not due to the writings in the New Testament stating that there is a link. It is more that any being who is against Christ, including those in Revelation, are likely to deny the Father and the Son and deny that Jesus came in the flesh, so, it isn't difficult to find numerous antichrists throughout the past 2,000 years that Christians could identify as being an antichrist and since, for each generation, their time was, to them, the end of time, because the future hadn't happened yet, it was easy for them to think of these antichrists as potentially being the beast or false prophet of the end times described in Revelation.
Over time, this traditional link between antichrist and the beast or false prophet became very strong, in spite of not being stated in scripture and more tradition has grown up around linking antichrist with the beast or false prophet, creating traditions upon traditions, upon traditions, not of which is substantiated by scripture or any other early writings from the Christian community.
I replaced some of the NiMH cells in my Prius traction battery by buying some Prius traction battery cells on eBay for $20 each. Still working fine after 2 1/2 years and a lot cheaper than buying a refurbished traction battery for $3,000. My Prius is 2006 so any cells from the Gen II models (2004-2009) work fine.
Earlier in this video he gives his opinion on the IBM PS/2: https://youtu.be/yoAH1aHmwR0?t=655