If I were part of the above conversation, my opinion would be that the home language does play a vital role in the acquisition of a first additional language. I would support this opinion with the following evidence:
Firstly, research shows that there is a strong correlation between proficiency in the home language and the ability to acquire a new language. Studies have shown that individuals who have a strong foundation in their home language are more likely to transfer skills and knowledge to a new language. This is because language is a cognitive skill, and learners need to develop solid cognitive structures before they can assimilate new information.
Secondly, the home language provides a cultural context that is necessary for the acquisition of a new language. Language and culture are interrelated, and learners need to understand the cultural context of a new language in order to fully acquire it. The home language provides this cultural context, and learners who have a strong foundation in their home language are more likely to understand cultural references and linguistic nuances in a new language.
Thirdly, learners who are encouraged to maintain and develop their home language are more likely to have a positive attitude towards a new language. Language is closely tied to identity, and learners who are able to maintain a connection to their home language and culture are more likely to approach a new language with a positive attitude and a sense of pride in their multilingualism.
In conclusion, the home language does play a vital role in the acquisition of a first additional language. It provides a cognitive and cultural foundation that is necessary for learning a new language and can help learners to develop a positive attitude towards multilingualism. Therefore, it is essential for educators to value and promote the home language in the classroom as a means of enhancing the acquisition of additional languages.