For 17 years he played weddings, dive bars, and cruise ships, writing songs that mostly went nowhere. The exception was French Kissin' in the USA, written for Debbie Harry, which hit the UK Top 10 in 1986. The Teenage Mutant Ninja Turtles theme was his, too. By 1990 he was on the Roseanne writing staff, co-executive producer within two seasons. Two and a Half Men in 2003 locked in his formula: ensemble comedies built around one impossible person to work with.
The Charlie Sheen meltdown in 2011 is what most people remember about Lorre. Two and a Half Men was TV's top comedy when Sheen went on a national media tour lobbing antisemitic slurs at Lorre, got fired, and CBS replaced him with Ashton Kutcher. The show ran four more seasons. The Big Bang Theory ran until 2019. At 73, he has Georgie & Mandy's First Marriage on CBS and Bookie on Max in production simultaneously. He cast Sheen in Bookie. Make of that what you will.
The vanity cards are the tell. Since 1997, every show he produces ends with a flash-frame text card he writes himself, on whatever's on his mind that week: divorce, mortality, ambition, petty resentments. Most viewers never see them. They flash for under a second and live at chucklorre.com. When he announced he'd stop writing them for Bookie on Max, he kept writing them anyway. That's either a very long bit or the most honest thing about him.