Gould was not arguing against evolution, he was arguing for his own ideas about how evolution happened.
The idea of Punctuated Equilibria is that speciation occurred via Mayr's mechanism of allopatric speciation. A small population would be cut off from the main body, and would rapidly evolve through drift and differing selection pressures. In some cases the new species that resulted would be able to expand past the barrier that had isolated it and replace the parent species.
Since this evolution would take place in a relatively small population, and a restricted geographical area it would be expected to be usually absent from the fossil record.
However, according to this view the "missing" fossils would be intermediates between palaeontological
species. Intermediates between higher taxonomic groups should still appear, in accord with evolutionary theory. And this is what we find.
The fossil record, therefore, provides very strong evidence for evolution.