I do not think it would be an improvement. When you watch a replay in slo-mo, there are a lot of things that look like intentional deaths but are just panicked responses, misclicks, or terrible decisions. Hindsight is 20/20, and chances are good that a half-dead Malphite fleeing from a full health fed Graves/Lulu combo honestly thought that turning around to ult them was a good idea at the time. Looking at a play under a microscope makes the dumb decisions look impossibly dumb, to the point that you might conclude they were intentional even when they weren't.
Besides, people who troll in subtle ways are still going to get caught eventually because they display a consistent pattern of toxic behavior. You don't need replay evidence for that.