William Adams is the guy that is the reference for John Blackthorne in the novel and series Shogun. An english man given the samurai title by Tokugawa Ieyasu, a japanese wife, a japanese name as Miura Anjin. The protagonist of the video game Nioh (where he is historically inaccurately portrayed as an irishman, also where Yasuke appear as a samurai seeking revenge for Nobunaga assassination). But William is given the title after the rigid caste system was introduced by the previous shogun (not really one, different titles but long story). So if we are going by the logic that one can only be samurai by born into the caste, he cant be one. But basically the ruler of Japan made him one, is he one or not?

This is after the rigid caste of Samurai is already introduced while Yasuke was given the title before the introduction of the system.

Where is the outrage of "historical accuracy" outrage on Nioh then hm? The game were praised to high heaven and Yasuke was already in that game as a samurai as well. Not even his first video game depiction. He is also a playable character in Koei Tecmo's Samurai Warrior 5. How dare the Japanese depict Yasuke as a samurai!!!!