I just noticed that Gordon Kane has recently published a second edition of his 2017 String Theory and the Real World. Columbia doesn’t seem to yet have full online access to the second edition, but one can already compare the two editions in a few places. For instance, on page 1-5 of the 2017 edition one reads
The LHC is now working in a region of energy and intensity where well-motivated theories imply superpartners could be seen by late 2018.
There is good reason, based on theory, to think discovery of the superpartners of Standard Model particles should occur at the CERN LHC in the next few years.
The corresponding first chapter of the latest edition has:
The LHC has so far just entered the region of superpartner masses predicted by compactiﬁed theories, which ranges from about 1.5 to ∼5 GeV (we’ll discuss that range later). Those values are the only physics predictions, rather than just speculations. The LHC will run with higher luminosity after an upgrade, beginning in late 2021 if pandemic work stoppages do not delay it. That increases the possibility of discovery, though not very much. A higher energy collider is needed. From what we know now, a collider with twice the LHC energy range would probably sufﬁce, and cover the region of gluino masses to about 5 GeV.
The concluding chapter of the 2017 edition tell us:
The compactiﬁed M-theory implies that three superpartners (and only three) will be observed at the LHC in the current three-year run (assuming the full integrated luminosity is achieved). These are the gluino and the charged and neutral winos.
Presumably he’s talking about the LHC Run II (2015-18) which did meet its luminosity goals, without any hint of the three superpartners. I don’t yet have access to the later parts of the 2021 edition to see what they say about this.
This isn’t the first time Kane has published multiple editions of ever changing “predictions” about supersymmetry. At one point I compared the 2000 and 2013 editions of “Supersymmetry and Beyond”, you can see the results here.