My discovery of jazz coincided with the launch of "Jazz FM" here in the UK, around 1993/94. The daytime programming was distinctly lacking in jazz, but the evenings were pretty good, especially "Dinner Jazz" (you can imagine what it was like!). After a year or two it rebranded to "JFM", which meant less jazz, then I think it was taken over and rebranded "Smooth FM", which was as bad as it sounded.
Still, for a year or two, you could actually hear jazz on the radio. Jazz FM's slightly older cousin "Classic FM" is still going, playing Classical music's greatest hits and adverts for very middle-class folks on rotation.
As far as I know, BBC radio still plays "Jazz Record Requests" for an hour a week, the other 167 hours being strictly classical music.