FibreChannel and Ethernet are pretty narrowly purposed towards networking.
FireWire was narrowly purposed towards low latency, high bandwidth transfers. That's why there was never a FireWire mouse or FireWire printer ports. It was overkill for these purposes. It was never designed to connect any and all peripherals. You are completely missing this point.
In theory they could be competitors to USB and Firewire and Thunderbolt but in practice they generally are not. You can do things like drive a monitor over Ethernet but people rarely do so. Similarly you can connect to a network over USB or Firewire or Thunderbolt but in practice people rarely do.
Oh really? Search for Thunderbolt dock. You don't use TB like this but many others do.
Thunderbolt on the other hand is being aimed at video and storage much like Firewire is/was. USB overlaps with those use cases fairly heavily.
Again, it is not. According to Intel and others it is aimed to almost expose PCIe bridge to connections rather than replacing USB. USB again cannot do what this. It adds a layer of complexity on top of it.
Virtually everyone has USB storage and USB monitors have become a thing. I have a USB monitor I use fairly often and it works great.
Since when? No one I know has a USB driven monitor so it cannot be everyone. Yes they have monitors that have USB ports but these are to use as a USB hub. The input is VGA, DVI, or HDMI.
Which matters not one tiny bit to most users. The few who need the modest advantages of an old version of USB over an older version of Firewire have it available to them. The number of use cases affected is pretty much the very definition of niche.
Again you are completely missing the point. If you need sustained transfers like digital video back in the day, you wanted a FireWire not a USB. That's why professional used FireWire long after everyone else stopped using it.
I could do the same thing using Thunderbolt but it would cost me a LOT more money to do it plus I'd still need USB for the mouse and keyboard.
How the hell is TB going to cost you a lot more money? If your laptop has it, then it has it. Now if you don't have TB and you have to get a new laptop to get it, that's a different story. But if your laptop didn't have eSATA or USB 3, then you are going to have to get a new laptop to get it, it's more expense than your old laptop. A TB dock also has USB ports, BTW.
However the latest incarnations (3.0 & 3.1) of USB are fast enough that they can do video too for the most common use cases out there.
Again there is a reason why professionals are getting TB devices.
Thunderbolt is technically better but there is a strong chance that won't matter any more than it did for Firewire. Anywhere USB and Thunderbolt compete I don't think Thunderbolt will fare well even though most of us would probably prefer it.
Other than the fact that Intel is the one pushing it and is part of their ultrabook specification? Other than most of the laptop manufacturers are starting to make laptops with it?