Bumrah is definitely an integral member of the Indian team, across the different formats. But that doesn't mean that India can't win matches without him. Honestly, I didn't thought that Bumrah was needed for the Lankan tour. But then things didn't turned up that well. Siraj was inconsistent, and at times he leaked plenty of runs. Arshdeep Singh and Khaleel Ahmed are still not up to the level of tier-1 bowlers. Ideally the BCCI should expand their pool of pacers and think about other deserving bowlers. Arshdeep, Khaleel, Avesh.etc have got enough chances till now.
Bumrah is good bowler but it does not mean the Indian team is nothing without him. They have Virat Koli and Rohit Sharma, also when the Indian team won the Asia Cup 2023 then there was a lot of hype for Muhammad Siraj as he picked 6 wickets in the final, so where he is now?
Why he is not performing? Just over confidence.
In short, the Indian team doing action then they got a reaction. In the first innings of the last match, they were playing with full aggression and disrespecting to the team of Sri Lanka but then as Sri Lanka started to take Indian wickets, it had altogether another level of revenge.
. Except of him, Shubman Gill, Virat Kohli, Rishabh Pant, Sheryas Lyer, Axar Patel, everyone is not in form and they take ODIs like test match and fastest they are losing wickets, also not with the good and high strike rates. They are playing slow and Shivam Dube has also done nothing in this match too, i think Shivam Dube is only able to play test matches or leagues. 
