Ah, I didn't notice the key detail - the downtube mounting bit. So you can swing the bars around and the stack of pizzas don't move, leaving my toppings intact. You're right about the cost though - that's like 1/3rd of what I paid for the whole bike :S
I’ve seen front platform racks that Strathclyde to the head tube. Pretty sure one had a ball joint or something so you can get the angle just right. Couldn’t find anyThing to back up my claim though.
This thing that mounts to the downtube? Ugly, expensive, bulletproof. I had one for a while.
https://www.dutchbikebits.com/azor-steco-frame-mounting-rack