Shinichi Mochizuki developed a new theory (IUT) which eventually yielded a proof to the abc conjecture. I believe he largely developed it in isolation and thus when it was published it took years to bring the rest of the community up to speed. Not sure if he doesn’t read other’s papers but maybe this is what’s you were thinking about?

1. https://en.wikipedia.org/wiki/Shinichi_Mochizuki

2. https://en.wikipedia.org/wiki/Inter-universal_Teichm%C3%BCll...

3. https://en.wikipedia.org/wiki/Abc_conjecture