“Christian broadcasting” is generally run by Protestants, many of whom are opposed to Catholic teaching, and they may not even consider Catholics to be the same as “Christians”.
I think Catholic presenters are better off staying out of “Christian broadcasting” ventures, since there are enough Catholics to support all-Catholic all-the-time media. We don’t have to jockey for a time slot on a station run by non-Catholic denominations. We also don’t have to worry about sharing air space on a station that might air programs that conflict with Church teachings. We have EWTN, Relevant Radio, WAOB Radio, probably other stations, all our own, and best to stick to them, especially now that we can listen online wherever we are.