The emergence of AI writing assistants has raised concerns about their potential impact on language diversity, preservation, and education. This paper examines the capabilities and limitations of AI writing assistants in generating dialectic text in response to academic and professional writing prompts. The study uses a concordance tool to conduct N-gram and keyword analyses on texts generated by AI writing assistants to examine the collocational patterns and linguistic conventions in AI-generated text productions. The results suggest that AI writing assistants rely heavily on Standard American English (SAE) conventions. Pedagogical implications include integrating language technology to promote language diversity and preservation and utilizing register-diversified corpora to enhance students' understanding of language beyond SAE. This study emphasizes the importance of critically evaluating and revising AI-generated content and contributes to a better comprehension of the potential role of AI writing assistants in academic and professional writing. [Note: The volume number (34) and publication year (2023) shown in the footer on the PDF is incorrect. The correct volume number is 35 and correct publication year is 2024.]