DV cameras were the one and only practical consumer application of firewire,
For years, firewire buried usb in terms of hard drive transfer speeds. (solid 800mbps vs laggy 480mbps) But it was during this time that PC motherboard manufacturers stubbornly refused to put firewire ports on their boards. Also during this time, it was difficult to impossible to boot a windows computer from an external drive. These factors led to almost a decade of time where the macs were the only computers that commonly used high performing external storage. (and not just for video) The windows users literally didn't know what they were missing, and most remained blissfully unaware. A few I know installed firewire cards and talked to me like they'd just discovered this amazing hidden technology that nobody else knew about.
Processor and controller advances (both in the computer and in the external drive controllers) during this time slowly removed the lag, and I suspect that's why it took so long to get USB3 out the door, they just weren't in enough of a rush to innovate. There was no push from the consumer side, and no one wanted to be the first to add FW as a standard option. The benchmarks I ran as early as 2012 were still running into slow controllers. There were a specific set of common speeds, determined by which chipset the manufacturer happened to be using. Speeds were now usually either 26 or 36 MB/sec, although there were a small number of them running at 39 and unbelievably still at 18. During this entire time, firewire 400 has been running at a consistent 39MB/sec, (fw800 at 79MB/sec!) and at the end there was about a 50/50 split between 36 and 39MB/sec on new USB adapters.
So then USB3 is announced and the world is buzzing. So I asked, "If you wanted higher speeds why didn't you just get firewire?" "Firewire? What's that?" "Nevermind...." But by the time USB3 came out, thunderbolt was hitting the stage to be the new usb dominator. USB seems to be doomed to be a generation behind. For the first year and a half it was almost impossible to find a USB3 drive that actually performed at speeds substantially faster than firewire 800, because most of them were trying to keep costs down after changing to USB3 by using slower hard drives. 90 and 130MB/sec HDDs were the norm in most of the early USB3 enclosures, but hey, they got to stamp "USB3!!!" all over the box and get the suckers to buy them without reading the fine print. The enclosures that had actual fast drives in them were more expensive and so were mostly overlooked. We had to endure years of "USB3 speed" flash drives that were below USB2's maximum speeds for exactly the same reason. The "premium high speed" flash drives cost 2-3x as much, and while they read faster, they still had slower write speeds.
There's just a large chunk of the demographic that wasn't seeing the faster alternatives. But at this point the storage, even though it's much faster, has been surpassed finally by the interface. I have a Lacie 500gb ssd with dual USB3/TB interface, and both of them top out at the same speed of 438MB/sec, which appears to be the SSD's maximum speed. I'd need to have an SSD raid with fiber-channel grade speeds to do a comparison now, which I don't have. So for now, for me at least, they're effectively the same. The speed of home-grade networking (gigabit ethernet) has become the bottleneck now, but this time it's affecting us all equally. (438MB/sec requires about a 4gbps connection to properly saturate, even dual-link gig ethernet just isn't up to the task)