While that may be the case, they still seem to be the best (quality) around.
I wonder. I've had more Tyrwhitt shirts rip on me than any other brand. However, that's likely because i wear them more than other brands. Their material is fairly thin, and starts fraying pretty quickly in areas. They really aren't built to last. They shouldn't be considered premium quality.
However, they do look pretty decent when new, come out of dryer basically ready to wear, and for some reason they have the best fits. I've tried to find alternate brands, but always end up coming back to them, much as I mutter under my breath when I order them. The fact that the pricing is pretty consistent for the past number of years is a nice perk too. I don't have to wait for sales or stock up when I don't need yet - when i need them, they're there to order at the same 3/$100 that they always are, with generally reasonably quick shipping.