For low speed flows like in F1 the viscous effects are much larger and this can make flow prediction more difficult. It’s actually pretty easy to predict the shockwave pattern from 1D theory without the need for CFD [0]. The boundary layers are much thinner and you can assume inviscid flow at first. At hypersonic speeds the interactions get more complex however and you’re dealing with a lot more materials science challenges so CFD is important in predicting thermal loads and shock boundary layer interactions.
[0] https://en.m.wikipedia.org/wiki/Oblique_shock