Green card abandonment and travel visa issuance concerns

My mother obtained her U.S. green card in 2019, and for the following 3-4 years, she stayed in the U.S. long-term for 6-9 months at a time, living fairly regularly.

However, starting last year, due to personal circumstances, it became difficult for her to stay in the U.S. long-term, so she adjusted her pattern to stay about 5 months in Korea and 1 month in the U.S.

Recently, when my mother re-entered the U.S. (LA), she was asked during the entry inspection how long she’d stayed in Korea, and she explained that she had to stay longer in Korea because my grandmother was ill. The immigration officer then took my mother to a separate room and warned her that if this stay pattern continues, there could be legal proceedings, and that her green card could be revoked, before letting her enter.

Given this, since it seems my mother won’t be able to stay long-term in the U.S. going forward, she’s considering voluntarily abandoning her green card, and I understand she would file Form I-407 (Record of Abandonment of Lawful Permanent Resident Status) for that.

In this case, she would need to apply for a new visa for future U.S. visits — I’d like to know if voluntarily abandoning the green card would create any disadvantage for future visa issuance or entry.

Also, if there’s anything to be careful about, or a specific process, when applying for a regular tourist visa (B2) after filing I-407, I’d appreciate the guidance.