We have many powders available today, perhaps too many. A lot of these will duplicate the accuracy and velocity results of other powders that have been around a long time - powders we are familiar with and comfortable using.
The only "lament" (if it really is one) is having to start from the beginning with load development using a new powder or powders we are not familiar with. That's not a big unpleasant chore unless you have no real interest in handloading.
It may take a little work, but any discontinued or hard-to-find powder can be suitably replaced with a powder that is actually available. At least, that's been my experience so far.