TBH, USB bandwidth is mostly a non-issue, as long as you don't run oodles of audio channels. You can run more than 100 audio channels in parallel over a USB 2 connection, so as long as you have a dedicated USB port for your audio interface, bandwidth is typically not an issue.
If we look at a typical audio stream of 48 kHz with 24 bits resolution, this gives us a data rate (bandwidth) requirement of 1,15 megabits per second. USB 1 has a capacity of 12 Mbit/s, so it is good enough for stereo or four channels, but more will drive it to its limits.
When we get to USB 2.0 (high-speed) , we have a bandwidth of 480 MBit/s, so sending 40 and more channels over USB 2.0 is not really a problem - with this, you address most realistic usage scenarios.
This may be true in general, but let me chime in with something.
I'm a bit of a PC nerd, and whenever I've bought a PC, I've bought it in parts and assembled it myself. I just say that to say that I take a keen interest in computer specs. I've stumbled over the fact that a lot if not most (all?) PC motherboards have the USB inputs arranged in pairs, where each pair is controlled by a chip. I think one USB chip (and it's two connected inputs) make up a USB bus (??). And it seems very commonplace to use different chips for the various busses. I don't know if it's about cutting costs, so there's a high performance "good" USB chip for the first few (neccessary) sets of USB inputs, and then a cheaper and worse-performing chip for the "surplus" ones. But at the very least, when you connect your interface to a USB connector, it matters what is connected to the other connector(s) on the bus. Or in other words, what's connected to the USB input next to it.. My motherboard is nothing fancy and cost about $300 when I bought it. It's not cheap but not high end either. Maybe the different USB inputs are designed for different purposes, although no motherboard documentation I've ever read has ever stated that "this USB is better to use for such and such device". But that's how it actually is in my experience. My Kemper, my Focusrite, and back when I had a Helix, they would behave differently depending on which USB input I connected them to. Certain inputs would always result in problems updating or transferring presets, or trying to record USB audio. While others have always been reliable, and still are to this day, about a decade after I purchased the computer.
I've noticed the same for the SATA (hard drive) connectors on the motherboard. Mine has six SATA-connectors for hard drives, and they are arranged in pairs, and each pair is controlled by a unique controller chip. So three different chips, in other words. I remember having the same problem when trying to use a high speed SSD hard drive. There was a huge performance difference depending on which SATA connector I used. One pair let it reach its advertised performance, one pair of connectors cut the performance in half, and the last pair of connectors would not even recognize the disk. They would however work fine with optical HDDs (which don't come near SSD performance).
So long story short, different connectors on motherboards often have different controller chips, which is why customer support will often advise you to try different USB ports. And then you might be like "what the hell would that achieve, USB is USB right?" to which the answer is "actually, no, it's more complicatred than that". Bandwidth is one thing, but with hard drives for example, you would differ between transfer bandwidth of one big file, and of a 1000 small files. A hard drive can be good at one but not the other. Likewise, you can be below the max bandwidth of a USB bus but still stress it's ability to process by effectively "DDoSing" it with tons of small operations. Poorly explained but I think I made myself understood. Just something to keep in mind.