You really don’t get any bigger or more influential in the various speculative fiction genres than Ray Bradbury. Whether you’re a fan of his work specifically or not, there’s no denying how fully it shaped what was to come afterward. None of us who are into sci-fi/fantasy–whether as writers or as fans–would be precisely where we are without him.
Rest in peace, Ray, and thank you. Our worlds, real and imaginary, are better for having had you in them.