How can be someone 2000+ and making 4 blunders?

@Subomega
They didn't play "horrible", on the contrary
If you "needed to look a few times" then its not blunders and very reasonable for a 3 minute game.
In blitz the point is not to play perfectly but to play ok and fast (thats why some people prefer classical and its fine of course)
I'm sure they're aware about king safety but its always a balance with available choices, and material and strategical considerations.
a4 is not a bad move (gotta stop a4 from black)

You are right. Weakening the king safety for the privilege to waste tempi and block your bishop is brilliant.

First blunder: white missed a tactical opportunity to win a pawn with a Zwischenzug. For the second time in a row (although the first time was slightly more complicated). Easy to miss in blitz.
Second blunder: apparently winning the exchange for a pawn was bad. Black's knight was really powerful, and white's bishop becomes really powerful with the knight gone. Also, apparently ...b5 was especially good - compared to any other move, Nd3+ would have only been a mistake rather than a blunder.
Third blunder: White could have kept a dominant position by improving his position with several slow moves while black can do nothing. Instead, he played an attacking move allowed a complicated draw. Black is in severe time trouble and doesn't go for it (fourth blunder)
Fifth blunder: now white plays a slow improving move when he should have liquidated into a better endgame.
Seventh blunder (black had played another bad-but-not-obviously-disastrous move with 13 seconds left): white misses a nice quiet move that would have prevented black from getting out of the bind.
Last blunder: well black had to play a move so he did. He was going to lose on time anyway.

@Subomega
It doesnt lose a tempo as a4 from black would have gained a tempo on the queen. a4 slows down greatly black's expansion with limited weakening of squares
blocking the bishop?? how does a4 blocks white's bishop? (or am i feeding the troll?)

I ment black f5 and e4 pawn. Plus it doesnt do anything active anyway.And to white who cares about expansion, opening lines is much worse.

Even though they are both way better than me, they look like patzers, that why i wonder if you are trolling.

a4 wasn't a bad blitz move. It delays black's attack, while white's attack has already started. White shouldn't have castled queenside in the first place, but he was probably overoptimistic about the power of his own attack.

7...Ne4: black had already equalized (it was a thematic tournament, I hope the Queen's Gambit isn't part of white's normal repertoire) so naturally as the stronger player he wanted more. Even objectively not that bad. ...f5 was the only logical followup; black didn't have king safety problems until later, when he tried to attack but didn't attack right, and allowed white to control e5 while keeping the queens on the board (and letting white's queen have a good square on d3).

Ok either you played the game with other accounts or you are joking, because nothing you guys say makes any sense

@Subomega
well you were answering my comment where i talked about a4 which is not a bad move : black's expansion could be quite annoying as it would weaken white's queen side much more significantly than a4 (make a defensive move to avoid making several later)
as for Ne4 and f5 it might be questionable but the idea is not outlandish : as with the Lasker variation (QGD), you exchange pieces and loosen the pressure against minor positional concessions. It's not optimal here as the bishop is already on g3 but its still sensible. Plus you might get f4 at some point and if you can play Be6 your bishop is a very decent piece and cover the opened diagonal