I don't think that Ryne is necessarily them reacting to criticism about Minfilia.
It fits in well with the Amarot conflict. You have a similar situation. Either the old Minfilia can return or the new Minfilia can flourish, but not both. At first Thancred wants to restore 'his' Minfilia at the expense of Ryne, but eventually grows to embrace Ryne and let go of Minfilia.
A foil to Emet-Selch who cannot let go of his old world and despite trying to bond with mortals, cannot bring himself to accept the current world and wants to sacrifice it to restore the old.
So it feels to me like there's more going on here than a simple 'oh crap we messed up with Minfilia, let's make a new one.