Quite a lot of web rendering is done with non-integer JS Number types, aka FP64. You are right that there’s a 31-bit integer optimization, but once you have a non-integer in the mix, it’s FP64. Many GUIs some time ago would use FP32, but in 2026 there’s a lot more FP64 out there than you give credit for.
Right but I've never seen these fp64 computations show up hot in a profile. I'm not saying they're not used but most of the work in a general computer usage in terms of profiles is in scalar integer code.