This is largely a subjective argument. There is no objective way to measure how iconic a movie is. This argument simply lists favorite moments from the Prequels. By the same token, the Sequels also have plenty of iconic moments to praise. Plenty of people enjoyed the lightspeed ram scene in The Last Jedi, or the throne room fight from the same movie. Or how about the gut-wrenching moments between Han and Kylo/Ben in the first and last Sequels?
The Prequels have had a decade for opinion on them to soften, and for nostalgia to cover them in a favorable light. One cannot argue about what will be memorable about the Sequels when they have just come out. Time will vindicate the Sequels, and illuminate the gems they have to offer. The Prequels don't have a monopoly on icons post-Return of the Jedi.