This very much depends on the simulation. CFD historically used 64-bit, with extended precision used internal to an extremely small number of poorly conditioned operations, or with very stiff equations; today it's not at all unusual to use single precision or (strategically) mixed precision, depending on the problem. I think the strongest statement you could make about simulation workloads, rather than them "needing" a specific precision, is that they are usually properly analyzed to determine the needed precision, and then run at that precision.

ancient intel did 80 bit fp until your intermediate result was written from registers to memory. Since you typically have no control over when that happens, even in very low level languages like C, the 80 bit precision mostly had the effect of making your code produce different results on different compilers. If you needed 80 bit precision and deterministic results you had to write the algorithm in assembly.