TL;DNR: You keep ignoring both the point of the comments and the point of the TFA. This is about market prediction, not technical exploitation of a privileged access to market.
anyone can buy co-located rack space.
If you buy a co-located rack space you are using a PRIVILEGED CONNECTION to the market that and taking advantage of that using some algorithm: That's High Frequency Trading.
The all point of TFA and the comments was the OPPOSITE: To be in a NON PRIVILEGED position (as in, the same access time to market transactions as the median of the access time to market of EVERYONE ELSE) and to use machine learning to predict market moves in a long enough term so that the market access time was irrelevant.
Do you understand the complete difference between the two scenarios now?