Counterpoint: in real life, people, even important people, die abrupt and meaningless deaths all the time, and it's not only okay, but, to a certain extent, it's commendable for fiction to recognize and reflect that. If every single named character only ever died in profound, thematically important ways, that would inevitably result in rote and bloated storytelling.
Take Nick Fury, for instance. Sure, it's nice that he survived the events of The Winter Soldier and was around to... talk to Tony Stark in a barn in Age of Ultron, stand silently at his funeral in Endgame, and pester Peter Parker (or so Peter thinks) in Far From Home. But, outside of Secret Invasion, he hasn't really done anything major since his death scare dramatically raised the stakes in The Winter Solder. Maybe it would have been better for the overall story had he indeed died at that point.
As for Taskmaster, that minor character was hardly Nick Fury, so I must emphatically agree she should have gotten more screen time or nuance before being offed. A death was needed to establish tension, and her character was superfluous, so quickly eliminating her was absolutely the right storytelling call.