Tubeless feels softer at 30psi than tubes for me
That’s what I’d expect too! The tube rubbing against the inside of the tyre makes the carcass feel thicker and stiffer.
The main thing I notice with pressure is that a big reinforced tyre like my Trail King 2.2 Protection feels way harder (at the same pressure) than a skinny normal tyre like my XR-Mud 2.0 (the difference in size is much more than the 0.2″ the claimed sizes suggest). And my Magic Mary Super Gravity 2.35 feels even harder thanks to the dual-ply sidewalls.
On my 6″ full-sus I’m running 18-20psi in the Magic Mary up front and 24-26psi in the Trail King out back, (low when wet, high when dry). XR-Mud needs about 28psi in the mud and that wouldn’t be anywhere near enough pressure to cope with rocky downhills.
A fat bike tyre at 9psi feels amazingly hard! Funnily enough although the thumb test is useless at detecting what the actual pressure is in the tyre if you use a variety of tyre sizes and types, it’s pretty good at detecting what really matters – carcass deflection under load.