Linen is the oldest upholstery fabric there is and the least showy, and choosing it changes what a carved bed is doing in a room. Velvet reflects light and pulls attention; linen absorbs it and recedes. Put linen against carved teak and the wood becomes the thing you look at - which is the right order of priorities on a piece where the carving has been thought about this carefully.
The buttoning is set wide for the same reason. Close buttoning creates a formal, tightly geometric surface; widely spaced buttons let the fabric relax between them, and linen relaxes visibly. It is a softer effect, and it ages well because linen improves with use rather than wearing out.
The footboard panel is where our master Indian artisans put the work. It is carved in relief rather than pierced, which suits a piece meant to be quiet - relief carving reads as texture from across a room and only resolves into flowers and scrolls when you come close. That is a deliberate choice about how much attention a bed should demand.