Most of the ornament in Gothic churches went into the architecture itself. The stonework became light and airy, looking like a holy gingerbread house with an emphasis on letting light in. The statuary no longer took center space, but was used to highlight the beautiful windows. Carvings surrounded the arches, and sat atop the gabled spaces above arches. All of this was public artwork.
Rulers and the rich were able to have their own churches built, or donate holy objects to existing churches. Louis IX built the Saint-Chapelle to house his own collection of relics in Paris, and a piece of the Virgin Mary’s linen was donated by Charlemagne to the Notre Dame. Royal families commissioned Moralizing bibles to be illustrated for the masses, sort of like getting your kid into reading by givivng them comic books.
There is a lot of art representing the relationship between the church and the current king. The statue of the Virgin Mary outside the Reims Cathedral wears a large crown to show the connection, Christ is shown to be a descendant of ancient kings in statuary atop the church, and inside Melchizedek gives communion to Abraham.