Is "Yaseen is the heart of the Qur'an" a صحيح (authentic) saying of the Messenger of Allah, peace and blessings be upon him, bearing in mind that the Qur'an was not compiled during his lifetime?

The hadiths: "Yasin is the heart of the Qur'an" are weak, and none of them are authentic. As for the problem that the compilation of the Qur'an was delayed until the time of Abu Bakr and 'Uthman, may Allah be pleased with them, it is said that the compilation of the Qur'an has two meanings: The first: memorizing it in the hearts, and this was completed during the time of the Prophet, peace and blessings be upon him. The second: compiling it into a mushaf (written copy), and this was completed during the times of Abu Bakr and 'Uthman, may Allah be pleased with them. So, if the hadith is authentic, then the intention is that Yasin is the heart of the Qur'an as memorized in the hearts. And the 'heart' here does not quantitatively mean the middle of the surah, but rather because it gathers the essence of the Qur'an's objectives and meanings.