“I bought this dish in a thrift store, thinking it might be good for tacos. It wasn’t ideal. What’s its actual purpose?”
Answer: It’s a toast rack. Here we are used to hot buttered toast where my inlaws put the toast in this as there was a larger family, so it was usually cold by the time it was buttered.
Toast racks are a hang up from upper class homes, where the food would be prepared in a kitchen some distance from the dining room and then carried by the servants. To keep the toast-sweat off the toast the rack became popular.
You have to remember that hot toast was a very lower class thing, it meant you weren’t wealthy enough to have someone else make your food. The only time wealthy upper class people ate hot buttered toast was at public school, or university, in front of their fire with a toasting fork. Read a Victorian novel about public school and there’s always mention of a toasting fork.
Because we Brits are terrible social climbers we all wanted toast racks because that’s the ‘propper’ way to serve it… Its what posh people did.