I've been using this https://www.amazon.com/B-Land-Magnetic-Gooseneck-Universal-Compatible/dp/B07ZSFVDKZ/ in combination with 8bitdo sn30+ controller for playing on mobile and it is amazing. The tubes bend so you can wear it around your Neck and it the screen will hover right at the perfect height on your vision while you play with a fill controller, less wobble than the claw and it's cheap.
been staying competitive on Destiny 2 when switching from pc to my phone.
Wow in the first moment I thought "WHAT is this???" but good that you actually explained this, I could imagine it's very practical to lay or sit with it in the bed/sofa and play Stadia with it. Seems to be very relaxing. Thanks for the tip!