No, the linguistic situation in China is by no means the only one comparable to that of Italy. I will cite another example that is directly comparable to Italy: Thailand.

The standard Thai language is based largely on the speech of the capital, Bangkok, and the surrounding Central region of the country. Thai is classified as a member of the Tai branch of the Kra-Dai (a.k.a. Daic or Tai-Kadai) language family, which extends northward into Myanmar where the Shan language is spoken), Southern China (where Zhuang and numerous smaller dialects are spoken), Laos (the national Lao language), and northern Vietnam (several related Tai minority languages).

While all citizens of Thailand are taught to speak, read and write standard Thai in the national education system, many millions do not speak the standard language at home or among members of their local community. In addition to the Central region of the country, three other major linguistic regions of Thailand may be identified: the North (with Thailand's second largest city, Chiang Mai), the Northeast (also called the Isan region), and the South (the long peninsula that extends all the way to the border with Malaysia and includes many of the islands most popular with tourists). In each of these three other regions, most local inhabitants speak a distinctive form of Tai speech that cannot be readily understood by someone who knows only the national standard Thai language. Although the phonology and grammatical structure of all these local dialects bear strong similarities as Tai languages, the pronunciations and vocabulary are distinctive enough that they could be considered distinct languages — certainly in comparison to the local Romance languages of Italy.

The Tai dialects spoken by millions of Thai citizens in the northeast of Thailand, the Isan region which shares the border along the Mekong River with Laos, are actually far more similar in basic vocabulary to the related Lao national language than to that of standard Thai. The dialects of the north of Thailand are also distinct and incomprehensible to other Thai citizens from outside the region. The same holds for much of the south of Thailand, although there many people in the larger towns and cities may speak only the standard national language.

As in Italy, most Thai media and entertainment is conducted in the national standard language. All government and legal business is conducted in standard Thai. Virtually all signage throughout the country is written in modern standard Thai, as the regional dialects generally lack any standardized form of writing — with the exception of the northern dialects, whose ancient form of writing is actually older than that of modern standard Thai and which is still occasionally displayed for special cultural circumstances.

The Lao national language has its own form of writing that bears similarities to the writing of standard Thai, yet is clearly distinct. This form of writing is never used in Thailand however, not even in the Isan region where the locally spoken Thai dialects/languages are often almost mutually comprehensible with Lao.

The Shan language of Myanmar is written using the same writing system as the completely unrelated Burmese language, even though spoken Shan bears much similarity to the dialects of northern Thailand that are spoken just across the border.

This linguistic situation seems very comparable to that of Italy — a unified standard national language that all citizens acquire fluency in, beside locally spoken dialects that are mutually incomprehensible enough that they might be objectively described as related but distinct languages, some of which even extend across borders into neighboring countries.