The Red Devils surrendered the lead on three occasions during the goal-fest at Old Trafford on Monday, with Diallo having opened the scoring in the 13th minute of the match.
“Today, [the focus] was to win this game,” said Diallo to MUTV.
"So, we are really disappointed, but at the same time we take one point and then we're going to prepare the next game."
The 23-year-old will miss the next few matches for his club as he heads off to Morocco to play in the 2025 Africa Cup of Nations, where Ivory Coast will be defending their title.
"You can't see straight away in the dressing room, everyone was very disappointed because we know as a team, we can do much better," added Diallo.
"We knew we can win this game today, but [it's] a big disappointment that we take one point and [we're] thinking about the next game."
United will face Aston Villa on Saturday without Diallo and Cameroon's Bryan Mbeumo due to AFCON 2025 duties.
Manchester United are bracing for a tough trip to Aston Villa after midfielder Casemiro was ruled out through suspension, deepening a growing list of selection problems for manager Ruben Amorim.
AC Milan have taken a significant step towards signing West Ham United striker Niclas Fullkrug ahead of the January transfer window, with reports indicating personal terms have been agreed between the 32‑year‑old forward and the Italian club.
Enzo Maresca has said he remains fully committed to Chelsea and has moved quickly to refocus attention on the Carabao Cup quarter-final against Cardiff City, following his recent "worst 48 hours" remark.
Ruben Amorim has challenged Manchester United to become far more clinical after they shared eight goals with Bournemouth in a breathless 4-4 Premier League draw at Old Trafford.
