Was prayer obligatory before the Isra and Mi'raj, considering that the Prophet, peace and blessings be upon him, saw people being punished for abandoning it?

There were obligatory prayers before the Isra’ (Night Journey); Allah commanded His Prophet to perform the night vigil at the beginning of the Makkan period, saying: "O you who wraps himself [in clothing] Arise [to pray] the night, except for a little" (Quran 73:1-2). Some scholars mentioned that prayer was obligatory as two rak’ahs in the morning and two rak’ahs in the evening.