Alacritty is slower than Terminal.app..[1] perhaps placebo effects were/are in play?
There is also a plan[1] for making Alacritty's latency best-in-class.
> When people measure actual end-to-end latency for games on normal computer setups, they usually find latencies in the 100ms range.
And in that very sentence link to a latency test for a game that is notorious for being laggy, and even then it reaches 59.4ms latency. The same video they link, even says (at 1:32) that Overwatch has a button-to-pixel-change latency of about 15 ms! So where is this "usually 100ms" coming from?
Just because of this I don't really trust the rest of the article.