I observed prayer along with the Messenger of Allah ﷺ and with Abu Bakr, Umar and Uthman (may Allah be pleased with all of them), but I never heard any one of them reciting Bismillah-ir-Rahman-ir-Rahim loudly.

صَلَّيْتُ مَعَ رَسُولِ اللَّهِ ﷺ وَأَبِي بَكْرٍ وَعُمَرَ وَعُثْمَانَ فَلَمْ أَسْمَعْ أَحَدًا مِنْهُمْ يَقْرَأُ {بِسْمِ اللَّهِ الرَّحْمَنِ الرَّحِيمِ}

[AI] "I prayed behind the Messenger of Allah ﷺ , as well as behind Abu Bakr, Umar, and Uthman, and they would not audibly recite 'In the name of Allah, the Most Gracious, the Most Merciful' (Bismillah Ar-Rahman Ar-Raheem) in Surah Al-Fatiha."

صَلَّيْتُ خَلْفَ رَسُولِ اللهِ ﷺ وَخَلْفَ أَبِي بَكْرٍ وَعُمَرَ وَعُثْمَانَ فَكَانُوا لَا يَجْهَرُونَ بِ {بِسْمِ اللهِ الرَّحْمَنِ الرَّحِيمِ} [الفاتحة 1]

[AI] "I prayed behind the Messenger of Allah ﷺ , and behind Abu Bakr, Umar, and Uthman. They would not recite aloud the Bismillahir Rahmanir Rahim (In the name of Allah, the Most Gracious, the Most Merciful) in Al-Fatiha (Chapter 1)."

صَلَّيْتُ خَلْفَ رَسُولِ اللهِ ﷺ وَخَلْفَ أَبِي بَكْرٍ وَعُمَرَ وَعُثْمَانَ فَكَانُوا لَا يَجْهَرُونَ بِ {بِسْمِ اللهِ الرَّحْمَنِ الرَّحِيمِ} [الفاتحة 1]

Yahya related to me from Malik from Humayd at-Tawil that Anas ibn Malik said, "I stood behind Abu Bakr and Umar and Uthman and none of them used to recite 'In the name of Allah, the Merciful, the Compassionate' when they began the prayer."

قُمْتُ وَرَاءَ أَبِي بَكْرٍ وَعُمَرَ وَعُثْمَانَ فَكُلُّهُمْ كَانَ لاَ يَقْرَأُ {بِسْمِ اللَّهِ الرَّحْمَنِ الرَّحِيمِ} إِذَا افْتَتَحَ الصَّلاَةَ

قَالَ صَلَّيْتُ مَعَ رَسُولِ اللَّهِ ﷺ وَأَبِي بَكْرٍ وَعُمَرَ وعُثمَان فلم أسمع أَحَدًا مِنْهُمْ يَقْرَأُ { بِسْمِ اللَّهِ الرَّحْمَنِ الرَّحِيمِ}

[AI] I stood behind Abu Bakr, Umar ibn Al-Khattab, and Uthman, and all of them did not recite "In the name of Allah, the Most Gracious, the Most Merciful" when starting the prayer, like this.

قُمْتُ وَرَاءَ أَبِي بَكْرٍ وَعُمَرَ بْنِ الْخَطَّابِ وَعُثْمَانَ ؓ فَكُلُّهُمْ كَانَ لَا يَقْرَأُ {بِسْمِ اللهِ الرَّحْمَنِ الرَّحِيمِ} إِذَا افْتَتَحَ الصَّلَاةَ كَذَا