This guy knows a thing or two about business. Its a bold, yet brilliant idea to supply less than the quantity demanded, anyone with some kind of background in economics would support this. Clearly it has payed off though. By promoting creativity and quality through your products and not focussing on
quantity, you've created a relationship with your customers (rational ones) and athletes that keeps the brand going. In the long run, these qualities have allowed you to expand your flagship stores to keep the Jiberish legacy going.
Side note, I'm pretty sure that sales haven't decreased because 5XL is no longer available... haha
Anyways, Jiberish is brilliant, some people are irrational, and I'm looking forward to seeing some new, always-creative flagship stores in the next few years.
Cheers,
Max