My issue with this is that I doubt many people DON’T believe Jesus existed. There is enough evidence based proof of that.
Including Roman records etc. the issue is whether he was born to a Virgin as the Son of God. And if God the Father exists. Or God the Holy Spirit (3 in 1).
Personally I have no doubt. He did, and does. But many are disbelieving now because his representation of earth is a far cry from his intention or it’s true purpose.
And that follows a disbelief that the institutions that have governed us for centuries, still have ‘the people’ at the heart of laws they pass and things they do. Nobody believes it any more.
And that’s the real issue. Not just belief in god, but belief in anything. In community, in marriage, in love, in gender etc