IIRC, Chuck Smith has been loathe to set dates.
He may have speculated like Billy Graham did once that he didn’t see how Christ could return later than 1975.
Speculations are not prophetic pronouncements.
From what I read here, I find it hard to distinguish between Smith's words and "setting dates" - he calls it a "deep conviction", not silly speculation.
Even a deep personal conviction is still not a prophetic pronouncement.
However, the bucket-of-rocks brigade will always find plenty to throw rocks at other believers about.
Thankfully, Chuck Smith can stand before His Heavenly Father with cleaner hands than about any other well known Pastor I know of, besides Billy Graham.