I think you misunderstand what they’re suggesting. Their idea, as I read it, is that every night you can Maid Spy someone and permanently add them to the list of people you’re spying on (so eventually, you’re spying on everyone.) It’s definitely not a nerf.
I like the idea. And I think conspiring outside the night should be a risk.
(Also, this should be a given - when you’re converted, you keep all your spies regardless of what role you become. This would balance out the buff to Maid Spy and make it less valuable as a confirmation, since even an Assassin, Mastermind, or Cult Leader could continue to “prove” they’re a Noble. Additionally, it would free up some of Apostle’s abilities to be used in other ways, since they can use existing Maid Spies to prove that part of the Noble mechanics if challenged.)