Automating proofs is like automating calculations: neither is what math is, they are just things in the way that need to be done in the process of doing math.
Mathematicians will just adopt the tools and use them to get even more math done.
There are areas of mathematics where the standard proofs are very interesting and require insight, often new statements and definitions and theorems for their sake, but the theorems and definitions are banal. For an extreme example, consider Fermat's Last Theorem.
Note on the other hand that proving standard properties of many computer programs are frequently just tedious and should be automated.
I don't think that's true. Often, to come up with a proof of a particular theorem of interest, it's necessary to invent a whole new branch of mathematics that is interesting in its own right e.g. Galois theory for finding roots of polynomials. If the proof is automated then it might not be decomposed in a way that makes some new theory apparent. That's not true of a simple calculation.