I write software documentation, so I feel qualified to answer this question. In software, when we say that a feature is not supported yet (or not yet supported), we are implying that while the feature isn't supported right now, we recognize that this may be something we do in the future.
Often we use "Feature is not supported yet" or "Feature not yet supported" to give the impression to the customer that we know this is probably something that they will want in the future, and we are actively considering including it in the product, but it hasn't been implemented yet.
On the other hand, when we say a feature is unsupported, we are simply making the statement that the software won't do that. We don't imply whether we think it ought to, or whether we think it will do in the future. It is just a simple factual statement.
Simply saying a feature is "unsupported" doesn't suggest any reason. It could be any of the following:
- Because it was supported in the past, and support has be deprecated, or
- We recognize that it is a feature that we aren't ever going to be able to support (software built on the .NET framework is never going to get native support on MacOS), or
- Maybe we haven't looked into it yet, or
- Maybe we have almost finished developing this feature and it will be in the next release
We simply don't know because we haven't been given any context.