Yandex LLC (Russian: Яндекс, romanized: Yandeks, IPA: [ˈjandəks] ⓘ) is a Russian technology company that provides Internet -related products and services including a web browser, search engine, cloud computing, web mapping, online food ordering, streaming media, online shopping, and a ridesharing company. Yandex Search is the largest search engine in Russia with an estimated 72% ...
I think the difference is given in the definitions above; the difference between pervasive and ubiquitous is the difference between somewhere and everywhere. But if you add a qualifying prepositional clause, the difference goes away: "pervasive among the younger generation" and ubiquitous in the younger generation" mean the same thing.
I am unsure whether to use "a" or "an" in the following sentence: Video games have become a/an ubiquitous part of American culture. For me, saying the two sentences out loud makes "an" seem like ...
I wouldn't use so before ubiquitous. I would use ubiquitous alone and hope that readers would understand that I was using ubiquitous in the sense of "present everywhere in the defined area"—an idea that is stronger than either prevalent or so prevalent.
The difference between the number of mentions of "ubiquitous" and "omnipresent" is relatively small. I'd expect that because I personally find "ubiquitous" and "omnipresent" to be more interchangeable than "ubiquitous" and "pervasive" (I feel pervasive has a slightly different meaning).
'Ubiquitous' is largely synonymous with 'commonplace' and is poor stylistically in most sentences using both. 'Commonplace' is actually the more appropriate word to use here; it is more natural-sounding (in almost all contexts), and here invokes the 'familiarity has bred contempt' notion far better. Note that your 'used to be unique' constraint makes the answer 'ubiquitous' incorrect.