I've added content types to a list, and I want only 1 to appear on the "new" menu button. To do this, I've set only the single type to be visible on the "new" menu, and thus it is the default type. Well by hiding the others, they no longer even show up in the "Content Type" selection drop down in the item form.
This is not how I remember things working in recent memory. I'd expect all content types to be selectable in the item form. This is all in "Modern" SharePoint Online. Am I forgetting something or has this behavior changed?