I often think about how Maxwell's equations were simplified because quaternions were hard to deal with by hand. Heaviside reformulated them into calculus, which

I often think about how Maxwell's equations were simplified because quaternions were hard to deal with by hand. Heaviside reformulated them into calculus, which was easier work with and accurate enough for pretty much everything. But now that we have computers, which can trivially deal with quaternions, (probably even more easily than calculus) why don't we go back to using those formulae?