I never saw the Messenger of Allah ﷺ pray the forenoon prayer, though I myself pray it. The Messenger of Allah ﷺ would sometimes refrain from doing a deed, even though he loved to do it, out of fear that people would adopt it and it would then be made obligatory upon them.
ما رأيت رسول الله ﷺ يصلي سبحة الضحى قط، وإني لأسبحها، وإن كان رسول الله ﷺ ليدع العمل، وهو يحب أن يعمله خشية أن يعمل به الناس فيفرض عليهم.
Malik narrated it in the chapter on shortening prayer (29) from Ibn Shihab, from Urwa bin Zubayr, from Ayesha, mentioning the same. Bukhari narrated it in the chapter on tahajjud (1128) from Abdullah bin Yusuf, and Muslim in the chapter on the prayer of the traveler (718) from Yahya bin Yahya, both of them from Malik with the same wording.Then Malik narrated from Zayd bin Aslam, from Ayesha, that she used to pray Duha with eight rakahs, then would say, "Even if my parents were brought back to life for me, I would not abandon them." This has a break in the chain, because Zayd bin Aslam did not hear directly from Ayesha.Nasai narrated it in Sunan al-Kubra (484) with some additional detail, through the route of Asim bin Umar bin Qatada, from his grandmother Rumaytha, who said, "I spent the morning with Ayesha. When morning came, she got up and performed ghusl, then entered a room of hers and closed the door. I said, 'O Mother of the Believers, I have only come to you at this hour for this purpose.' She said, 'Then come in.'" She said, "So I went in. She got up and prayed eight rakahs. I do not know whether her standing was longer, or her bowing, or her prostration. Then she turned to me and struck my thigh, saying, 'O Rumaytha, I saw the Messenger of Allah ﷺ praying it, and even if my parents were brought back to life on condition that I abandon it, I would not abandon it.'"Imam Ahmad narrated it (25078) in abbreviated form from Waki, who said, my father narrated to us, from Saeed bin Masruq, from Abu Aban bin Salih, from Umm Hakeem, from Ayesha, mentioning it in brief. Umm Hakeem is Rumaytha, the companion who was the grandmother of Asim bin Umar. Mizzi said, "It is said that she is Rumaytha bint Hakeem." I say, other views have also been given.In Imam Ahmad's chain is Waki's father, who is Jarra bin Mulayh, concerning whom there is disagreement. Al-Hafiz said of him, "Truthful, but prone to error."As for Ayesha's statement, "I never saw the Messenger of Allah ﷺ pray the supererogatory prayer of Duha at all," she perhaps meant that he did not do it constantly, otherwise it is established in the sahih hadiths that he ﷺ did pray it, except that he did not maintain it regularly, out of fear that it might be made obligatory.