In Australia the two terms are certainly not interchangeable.

However such articles and general media reporting in Australia that use the term gun safety - we'd generally take to mean they are talking about gun control including the wider ramifications of laws regarding weapons that are either restricted or prohibited.

The term safety has IMO gained popular usage most likely due to the fact that many people in cities where much of Australia's population resides (where reasons like self defence is viewed as not a genuine reason for a gun licence) - thus they don't (no longer) have guns, there exists a strong view where less guns is seen as safer in the way that if there were 95% less cars in a city there would be less car accidents and thus better car safety.

In cities or large towns there's limited reasons to justify a gun licence with exceptions such as if they belong to a sporting gun club or a recreational shooter visiting rural hunting areas occasionally on their time off.