Effective on May 22, 2023 several restrictions have been lifted concerning flying while using BasicMed to fulfill the FAA Medical Certificate requirement.
On that date, those pilots flying under BasicMed may legally act as required crew members not just as Pilot in Command. That means that you will legally be able to fly as a safety pilot for someone practicing instrument flying while using a view-limiting device without the requirement to also be the Pilot in Command of the flight..
This change was tacked onto the regulatory change requiring commercial balloon pilots to possess a second class medical certificate when exercising commercial balloon pilot privileges. It was published in the Federal Register on November 22, 2023 (Docket 2022-25288) with a separate, specified effective date for the BasicMed changes.
You can read AOPA’s article on this change at: https://www.aopa.org/news-and-media/all-news/2022/november/17/basicmed-limitation-lifted