Buy a pair of ten year old $40,000 speakers for $4,000 or new ones at that price point?

Hi. There are bargains to be had on really high-end components that are more than a few years old. DACs change too much and we need the newer technology. How about speakers? I know it can depend on the specific model but in general is a 10 year old speaker system that was $40,000 in 2009 and now sells for $4,000 a better value than a new system that sells for $4,000 in 2019?  How much has speaker and crossover technology evolved in the past decade or so? (I posted a similar questions about amps in that forum). Thanks for all the input and wisdom.