Sure some of it might have been fine at 2.5 or 5 but those are relatively new and less commonly available.
Verizon's been issuing a wireless router with 10G WAN and several 2.5G ports and MoCA support that includes a 2.5G adapter and they use that across all their current connection types. I was delighted to see that when I got the router a couple years ago.
SFP+'s and fiber are cheap, like maybe 50 bucks for the SFP+ set and fiber. 10Gb PCIe cards are maybe ~$50 new on Amazon with Intel chips and cheaper on eBay - I bought used 10 Gb Mellanox cards for $25 each - "they just work" under FreeBSD and Linux.
Copper 10 Gb used to consume waaaaay more power (like 5+W per port!) and cost more both in terms of the SFP and cable. In reality fiber is more environmentally friendly as there is no copper, less energy used, and less plastic per meter. So my setup mostly consists of SR and BR optics and DAC's. The "DAC" direct attach cables are handy for switch-switch or short switch<->NIC runs. And I will continue to run fiber for the foreseeable future and actively avoid copper.
San Francisco checking in.
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.
How much would they need to cost before you'd consider it cheap? If you want CHEAP then 10GbE is not for you in 2026.
The Mikrotik switches [1] work technically speaking but they are quite difficult to configure. You have to pull them from your network, connect physically to a specific port, force your machine onto a specific IP, connect to a specific IP. I could not get this to work in macOS nor Ubuntu despite hours of futzing with it. They both kept infuriatingly overriding my changes to the IP. I was only able to get this to work on an old Windows 10 laptop.
Once you do get their web UI up, you pray the password on the sticker on the bottom works. Neither of mine did and I had to firmware reset both and find the default password online. The web UI itself holds no hands. It's straight out of 1995, largely unstyled HTML. While using both of my devices the backend the UI talked to would crash and log me out about every five minutes. Not every five minutes after log in. Every 5 minutes wall time!
The Mikrotik switches are also fanless, and 10GbE SFP+ adapters throw off a lot of heat. If you use more than one they overheat. You can just about get away with two if you put them on opposite sides but I would not recommend it.
I've also had very mixed luck with SFP+ module compatibility with this thing. I had a number of modules that refused to run at higher than one GB, hence my fighting to get into the UI. Despite a ton of futzing between logouts I was not able to get them to work at 10Gb and returned them.
I'll be honest, my Mikrotik switches have been infuriating. I replaced one of them with a Ubiquiti Pro XG 8 8-Port 10G and holy crap the difference is night and day. It just works. Everything worked straight from the box day one, I can configure it from my phone or the web, I highly recommend this thing.
The Ubiquiti switches are multiple times more expensive but if you value your time they're well worth the price. I still have two of the Mikrotik switches on my network but am completely intent on replacing them. The Ubiquiti is worth it for online configuration alone. No need to pull the thing from your network, test your changes immediately!
For writes yes 10GbE overkill but for for reads it's faster than 2.5GbE would be.
Sure there is 5GbE but most switches that support 5GbE support 10GbE.
~ 1 GB/sec seems about right for a long time. I can't imagine the basic files I work with everyday getting much more storage-dense than they are in 2026.
Last time when I checked, dual-port 25 Gb/s NICs were not much more expensive than dual-port 10 Gb/s NICs.
If you have a few computers with no more than a few meters distance between them, you can put a dual-port 25 Gb/s card in each and connect them directly with direct attach copper cables, in a daisy chain or in a ring, without an expensive switch.
For 40+ GbE or fibre I agree they are expensive, but at least you get full performance out of your system. SSDs aren't cheap these days either...