What is the jurisprudential ruling on limiting condolences to three days, and is this considered an independent reasoning (ijtihad)?

It appears that the specification of the three-day period for offering condolences is a matter of scholarly ijtihad (independent reasoning), and its basis is the hadith concerning mourning, in which the Prophet, peace and blessings be upon him, said: "It is not lawful for a woman who believes in Allah and the Last Day to mourn for a deceased person for more than three days, except for her husband, for whom she mourns four months and ten days." The purpose of offering condolences is to soothe the heart of the afflicted person, and generally, their heart settles within this period, so their grief is not renewed thereafter.