No, they don't do that anymore. I mean some people do, but in general creators have moved on to better things. There are many dedicated camera's now. The problem with side by side cameras is that they are usually too big to allow for the proper eye distance (around 65mm) so the perspective is wrong and also that the frame refresh is not synchronised which causes a small time difference between frames for left/right which can make people dizzy when things are moving.

These days there are several pro-grade solutions. Canon has a really nice dual fisheye lens for their R5 camera - https://www.canon.co.uk/store/canon-rf-5-2mm-f2-8l-dual-fish... , there's also some dedicated cameras in the pro-scene like the blackmagic ursa immersive: https://www.blackmagicdesign.com/products/blackmagicursacine... if you have 30k$ to spend :)

In the low-end people tend to mod 360 degree cameras by taking them apart and putting the two cameras side by side in a 3D printed enclosure. Reddit has a community about that: https://www.reddit.com/r/VR180Film . You can get a gopro max 2 now for 400$ or so and it does 8K (you need a really high resolution because the viewer will only see part of the recording at a time!). Though modding is difficult because they tend to be action cameras and glued shut to avoid damage from shocks. But the resulting image quality is surprisingly great.

And the streamers use cameras from https://www.calfvr.com I believe. Not entirely sure though.