It wouldn't actually be hard, but it's still more mathematical sophistication than 99% of the rest of the game I suspect, so he may not want to bother/not know how to use that part of C#.
I think more so than not wanting to bother with it, Steve may not want to introduce that degree of mathematical complexity into the game on pure game design grounds. A lot of the strength in Aurora's design is that it is built not on having a lot of incredibly complicated systems, but rather a lot of relatively simple systems (at least mathematically and conceptually) which interact with each other in complex ways to create interesting decisions and gameplay.
Probably the most complicated part of the game mathematically right now is missile design, and even that is just an extension of the engine design mechanics interacting with manoeuvre rating - the actual mechanics are not too complicated, the hard part is optimization which is true for many parts of the game.
Often it is the case that the optimization in pure mathematical terms is easy, but in practice the decision-making is dominated by interaction with other mechanics. For propulsion design, for example, while most who have played for a while know about the optimal 3:1 engine-to-fuel ratio many people will not use that ratio due to other factors beyond the simple mathematics, e.g. fuel consumption or RP conservation.
The point being, introducing a mechanic which requires the relative complexity of a linear algebra solver to work out is not necessarily in keeping with the apparent design philosophy of Aurora's mechanics. That may be a bigger concern for Steve than linear algebra being a little bit hard to program.