Well, the IRC protocol is all we have to work with. It would be impossible to implement an IRC client in a way that supports an unknown future protocol with unknown changes.
The support for /msg and /query -snxmd the way it is currently implemented is the ideal method.
One alternative, where any combination of the letters -snxmd is treated as a switch, and any -otherletters are treated as a nickname, is unpredictable and would make the situation worse. It would allow 120 possible combinations (which would increase if new switches were added) of -snxmd that would not be treated as nicknames.
Another alternative, to revert to pre-7.52 behaviours, and remove support for these switches, would return the behaviours to how they were, with /msg -s and /query -s/-n being supported. This still has the issue in that "-s" and "-n" are special letter combinations that are not treated as nicknames.
Since this issue only seems to affect users who /msg non-valid nicknames, specifically BNCs, we could accept breaking backwards compatibility and require that BNC scripts be updated.
