As first, I'm playing keyboard plus mouse.
When attaching a grenade launcher (GL) to assault rifle, pressing V during aiming will switch _only_ GL in my understanding.
However, switching night vision (NV) and Thermal Vision will be switched together. I mean, in during aimdown, please ignore NV and Thermo if pressed V key. Wildlands (and if my memories are correct, closed beta of Breakpoints) has no issue like this.
It's default keybinding or not, I mean, this problem was not solved by changing the NV key binding.
My GL swap on my assault rifle & NV/Thermal Vision work independently of each other since I rebound them. Might just be a quirky bug?
That said, yeah they def have issues with things during aim. Wildlands did a fantastic job of it - too bad for some reason BR didn't decide to follow in the footsteps *sigh*.