…supported JSON output anyway, the output side was done pretty much anyway.
Anyway, there are many other stories like that.
Suffice to say, in v257 there are now 19 Varlink interfaces/services, which we added in a short time, for various things that never had them before when D-Bus was our sole focus, because it was so nasty to add that.
(For comparison: we provide only 11 D-Bus API services at this time).