I know, I was the one that made the countless bug reports on it. When that didn't work, I tweet rickless myself to tell him about it since October, but he said that it would be a good thing to do when they are looking into making changes to Akali. And so here we are 3 months later when Riot has time to look into Akali, this is the first thing they did.
Details here: http://boards.na.leagueoflegends.com/en/c/bug-report/ErzYFuxe-gameplay-akalis-dash-travels-slower
But still, its technically a buff because that what it simply is. If Akali is performing poorly for 8 months because of a slower dash due to a bug, then fixing the bug to increase the dash back to normal will make Akali perform more strongly, which basically what a buff is.
I am not complaining about the changes to Akali, I am an avid Akali main since 2011 and have participated alot in discussing Akali's balance over the years since then. I really hated how they did the strikethrough change in 5.9, and for some reason, it messed up the dash speed when it shouldn't. The real fix would be to redo their strikethrough code so that it actually reads the missile speed the same way as a normal dash. The easy way would be to simply increase the missile speed up to until it matches the old dash speed.
Nonetheless, the dash speed shouldn't of got lower since 5.9, and it took over 8 months to fix it...that just sucks hard but atleast its getting fixed now for 6.3.