Zero copula is a common but not obligatory part of African American English grammar that can occur just about any time you could contract “is” or “are” to " 's" or " 're" in Standardized/General American English:

• “His name’s Steve” “His name Steve”
• “We’re leaving” “We leaving”
• “I know who that is” “I know who that is” (ungrammatical to contract, ungrammatical to remove copula is)

Regarding “gone”: In casual speech, the kind most people use everyday when talking to one another, vowels become more centralized and consonants are removed or articulated as flaps or taps or otherwise assimilated to better accommodate faster speech. This has been studied in English, Dutch, and German at least. Some examples are “going to” -> “gonna” and “I don’t know” -> “I dunno”, which have transcended phonology into our orthography. I’m not sure what process explains the “gone” variant, which is just “gonna” without the schwa at the end, but yes, many Black Americans say that.

The country broadly has what’s called a monolingual language ideology. English is prioritized above others. Multilingualism just isn’t viewed as a skill. And thus there’s no large pool of L2 speakers with which to interact regularly enough to learn and maintain an L2. I mean, they certainly exist, but the landscape is quite different from somewhere like Belgium or South Africa or, idk, most countries. Really anywhere where there’s like a home/cultural language, a market language (maybe a pidgin), and an official state language.