Foot melee infantry is the core of the game. Their ratio should be at the very least 50% of every game mode; especially in battle. Probably closer to at least 60% when you really think about it. The recent change in ratios is caused by a number of things.
1. Strong influx of new players from Steam Sales
2. Nerfing of Melee oriented classes (turn nerf, polestun nerf, etc...)
3. Less skill (both personal and teamwork oriented) required to play the classes that have overgrown their place. (cav, archery, etc...)
People are going to get up in arms about #3, but it's the truth. It's alot easier to run around kiting people slower than you with a bow (while being protected by melee) or by riding around couching people from behind with an unblockable, near instant kill attack;, while they are fighting someone else. We've all seen it. We all know it. Those who are objective can at least admit it.
That being said, it's nice of the balance team to at least acknowledge and admit they made a mistake by fixing turn speed (which a lot of people said would never happen) a little bit back to where it should be, but it's still not enough in my personal opinion. A good start but not enough. But as I said, I'm glad they at least admitted they went way too far with it.
Things will probably get a little more balanced (back to where they should be) when weapon speed gets universally buffed, but there will still be issues.
But yeah, I don't know how anybody could say there isn't a huge surge of cav and ranged players lately compared to the past. Best thing to do is look at why that is and tackle the problem from there.