Why customs rules need to factor in at least a decade of price rise

Every passenger landing in India from overseas, after completing immigration and collecting their baggage, has to pass through Customs, where goods beyond the permitted duty-free allowance must be declared through the Red Channel, else the passenger can simply pass through the Green Channel.
India’s duty-free baggage allowance was last updated in 2016, prescribing allowance limits on which no duty is payable for different categories of passengers.