This is the right place to ask. Actually, users would still be able to enable Save Password by manually editing spark.properties file and adding a line. Well, only sophisticated users would do that, but then they can share this with others. These Client Control settings are of “security through obscurity” type and it needs a major reworking to make it work properly.
I have filed a few tickets (for Spark and for Client Control as changes has to be done in both for new settings or changes in settings). But it can’t be applied retroactively to the current version of Spark. So it will only be changed in the next version. Unfortunately Spark is currently in a development stall (there are no devs to fix current major issues with 2.9.0). So i can’t tell when it will be released.
These changes are easy enough so i might be able to do them myself.