Jay Leno has put modern late-night comedy on blast, claiming the hosts are isolating half their viewers, just days after Stephen Colbert got the boot from CBS.

Billy Joel is opening up about a tough moment with longtime friend and tourmate Elton John. In the second part of the new two-part HBO Documentary, “Billy Joel: And So It Goes,” the “New York State of Mind” singer shared how John’s public comments that he needed rehab strained their friendship. “Elton had made a …