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Learn about the source first:

At first, pseudonyms and Roman characters were used in one-to-one correspondence, which was the Roman character used in James Plain/james black Book 1 edition, so it was called Plain (Black Book) Roman character. However, ordinary Roman characters are based on English pronunciation, which is considered to have many defects when used to represent Japanese. Therefore, 1885- Tanakadate Altltu designed Japanese Roman characters according to phonology theory. Japanese Roman characters based on phonology theory have been recognized by many linguists at home and abroad. However, it is unacceptable for English users. 1937, Japan-Cabinet Directive No.3-promulgated the Roman character directive based on both.

After World War II, under the rule of the United States, there was chaos due to the reappearance of plain Roman characters. 1937- cabinet directive No.3-abolished, 1954 was republished as-cabinet notice No.0/,and the use of Roman characters in plain style was limited to cases where international relations and previous practices were difficult to change. In 1989, the International Organization for Standardization (ISO) adopted imperative Roman characters as the ISO3602 standard.

Here's my opinion:

In fact, the black version is still popular with the Japanese people. For example, English names on Japanese business cards are basically spelled in black Roman. The trademarks of Japanese products basically use black English names. For example, Hitachi replaces Hitachi, Mitsubishi replaces Mitsubishi, and Fuji replaces Woody.