>solved the problem with a given reason

Edit: I just removed my comment because I failed at parsing this expression, and ended up replying to something you did not actually say.

Very interesting result indeed. The key was that the researchers developed an algorithm to automatically improve the efficiency of their SAT search - the 200 GB "proof" was just the logic equating their efficient SAT search with the original SAT problem - the output of their algorithm. The real magic was in devising this algorithm.

Once you have a finite problem (which usually requires human human), computers can just chew through cases.

There are Sudoku which (appear to be) beyond human ability to solve, but which computers will prove solvable within milliseconds, just by chewing through the options.