minor nitpick: I wouldn't call it stagnating. They were artificially inflated.
as an aside: for pricing, 20 years ago unmanaged 1G-BaseT ethernet switches were $20/port. That's the region 10G-BaseT switches occupy right now if they use realtek chips. And multiple sources confirm the realtek switch can do full line rate on all ports simultaneiously with a normal 1500 MTU
That corresponds to $50 and $105-130 in today's money.
Now you can get it 10 times faster with an OK management layer for $150. This is after a -long- time of 10gbps prices stagnating.
10gbps is unexpectedly cheap.