I've seen posts about "'metadata': { 'properties': { 'content-appearance-draft': { 'value': 'full-width' }, 'content-appearance-published': { 'value': 'full-width' } }" but I think this only relates to deprecated Content API
I also see users can set the default to "full width" on creating new pages... and this ALMOST works: when i create manually it works, but when i create with API it is still initially "small", but when i edit it it automatically goes to full width... assumedly the "draft" behind it is being set to full width but not the published version? With 6000 pages to create this isn't really an option