Im gonna give a crack at this since I weirdly happen to have a little experience with ALMOST this exact situation and not sure what your comfort level is with things like Linux and such but before I go all backstory etc, my suggestion is a weird one. If you are using
Blue Iris and a USB webcam directly.... check out ... and hear me out here ... The Dolby Voice camera - vcu9005-1 - model: cid1008. You can find these gems on ebay for like $5-15 depending on shipping etc. But the camera itself is pretty amazing its 4K@30 / 1080@60 / 120@720. under YUV2 and the specs on MJPG are also pretty good, It meets UVC requirements and I remember just plug and play and was able to even hit 60 FPS @ 1080 (if I recall properly).
Now I will say depending on your use case the others are correct and a IP camera will be much better due to things like built In low light / IR etc....
That Said If you'd like to hear a little of my reasons and such I invite you to read this as it may actually be helpful as I am revisiting this as I am planning to move some equipment around which will also modify what I am doing due to space.
So the reason I am using USB Cameras is for monitoring my 3d Printers. I happened to literally have one of those dolby cameras fall into my lap and research I guess they were doing a conference room solution right as covid hit so it got abandoned pretty quickly after. However, dolby being dolby the hardware is quite nice. So I was looking for something I could setup and use with BI since my orginal plan of using Octoprint went out the window due to the printers I use are not specifically (at the time) available for octoprint, it also didnt make sense to run a completely seperate camera system when I could feed these cameras into BI. So I turned to Logitech Cameras much like the 933. Infact I have 3x 920s and a 933 and something else, what I found out about that is that SOME of the 920s had the h.264 encoder in the camera itself. So, if you have that its by far the easiest. So check webcam specs for h.264 if you want the absolute best plug and play. At least in my experience. However, the reason you wont find many logitechs with h.264 anymore is they went away from that due to PC hardware / software becoming so much more powerful it was a non issue to conver MJPG or YUV on the PC vs the camera. So using linux and the V4l2 you can plug a camera in and see all the specs and thats where I saw there were a some 920s with and without h.264. So I had to figure a new way as I wanted to stream multiple cameras. Also, Raspberry Pi wasn't going to cut it at this point.
So while this is most likely beyond what anyone else would do or even want to do, I built a PC from old parts I had (4770K with a 1050 ti in it), installed Debian. Then using MediaMTX and GStreamer I was able to convert the YUV streams to h.264 and use RSTP to send the video to BI. I am sending 4 cameras currently (all those dolby ones... I bought like 10 lol), and the debian box is using about 30% cpu and less than 5% GPU But thats more because the transcoding isn't super stressful and uses about 80 MB of video ram for the transcodes. BI I setup as any other RTSP stream and its been great like the rest of my cameras.
Now I am thinking of moving my printers to a more enclosed space and the case I put my PC in to stream is justtttttt too big to put on the shelf the way I'd like. So based on measurements and such I am looking to see if I can run the same streams without the GPU, If BI will capture the YUV2 Raw streams etc.
I really hope this can help as I know how frustrating it is to not be able to solve a very one off problem as you can see here haha.