I don't think the sigils were restraints in the way you are implying them. What Yoshida says about them to me it comes off as a visible badge that can appear if their mask us lost. Since he gives an example of if someone were to pop out Ultima people wouldn't panic straight away and assume the use of high magics wasn't being used recklessly. Or like how some things were only accessible by the Royal Family of Allag. (Course that wasn't as secure once they started making clones. Just like the Vita Chambers of Rapture were only supposed to be usable by Andrew Ryan but also allowed DNA relatives.)

If they did actually restrain their power then I think it's in how strong of magics/abilities they can use. Which doesn't matter too much since the only time most convocation members quit is when they step down and take the retirement nap. It would be adjacent to any time a superhero with powers gets some kind of restraint placed on them or was given something that powers them down. Like the chip that was placed on Captain Marvel. She could still use her powers just not at full strength.

I don't think you'd have to try and convince most of the population to go with the Zodiark plan though. Ancient society to me at least comes off as a group that was highly conditioned for a long time to behave in a certain way. It doesn't come off as a place where you could go and take a vacation if you needed to. Sure you could step away from your work space for a day since that's technically what Hythlodaeus is doing. Yet it could be seen as him still working as he's playing the role of a guide to Emet. Even the WoL is seen as a slight deviation from the normal "familiar" due to being so "thin" of Aether and looking like the only convocation member that isn't a stick in the mud.

Not that I think Hermes was one. Just that after he thought he had lost Meteion his personality seemed to have shifted. We also know that the third time Azem disagreed with the rest of the convocation they ended up being branded a traitor and had a "You can't fire me because I quit!" type of moment.

Anyway this thread was made to talk about if people thought the top choice or a specific person was justified in what they did. Or if you viewed none of them being so. I'm not sure how anyone would have thought that we wouldn't land bad to having both sides run into the same wall again. Since you know we gave up on horse glue.