Foil is relative. The article doesn't provide much background on contemporary computer Go.

On Kgs where I play, the highest rated computers are at 5 dan. That is basically better than 99% of the players on the server which I think is the largest server in the English speaking world. Computer go has made considerable strides since 2009 [1]. The main impetus for this has been Monte Carlo Tree search[2]. Computers have not yet reached the level of professional Go player unlike Chess but progress from existing methods seems quite possible.

[1] https://en.wikipedia.org/wiki/Computer_Go [2] https://en.wikipedia.org/wiki/Monte_Carlo_tree_search