There are tons of misconceptions about mathematics, but the biggest and most baffling one is: that no new mathematics is being created, that the field is "done".
The opposite is true: there are more open problems than ever, and research is frantic in mathematics with hundreds of thousands of serious new theorems being proven every year by professional mathematicians, and entirely new mathematical vistas being discovered every few years.
In fact, the pace of research is so fast that we are now creating the foundations for databases of mathematical theories and their proofs in order to better classify and preserve them.