Yes and no.
Our Australian Broadcasting Corporation has had such auctions fairly regularly over the past decade or so.
The majorty of the gear falls into one or the other categories.
1) It is broken.
2) It is bespoke.
3) It is utterly obsolete.
4) It is obsolete but fools will still bid it up to an absurd price.
5) It is a piece fo really good kit but fools will bid it up to more than you could buy it for retail with warranty.
6) There are some gems that only you will see the value of and you'll go away with a bargain.
Speakers, I would be very suspicious of, rats make meals out of cones, even without that happening they'll quite likely have been thrashed.
There are bargains to be had. I bought an Otari 5050 for $50 that I used to generate a lot of income. Some of the old audio gear may contain components such a high quality line transformers that are quite valuable even today. I picked up a box of bits for $1 that contained a set of alignment tapes for old cart machines, those I donated to a local "PBS" style radio station that still used that cart system.
Another bargain was a Miller DS5 tripod for $300 that was almost new that we've had a lot of use out of.
The best bargain I saw someone get was a set of three robotic studio pedestals. He bought them for $2K and on-sold them to a Canadian broadcaster for $150K for spare parts.