Free Alternative to Lightroom? At least it used to be free for a while

I've downloaded this DXO Optics Pro 9 a year ago when they offered a free license for anyone who sign up their mail list before Feb 28th 2017, and I was one of them.
Downloaded and tried, didn't work as well as Lightroom so I just left it aside and barely touched it over the last year. Now I'm searching for solution to replace Lightroom and revisited this software, the function seems work fine, only that export speed is at least twice as slow as Lightroom and it does not support raw photo from A6300 because it is old. Here is a video of me trying out this software again after 1 year, quite fun to play with.