The article was published in 2016, and the authors extrapolated from 7 data points (!) over about 7 years of progress in the world record. This is obviously insufficient to project 30 years into the future.

https://pubmed.ncbi.nlm.nih.gov/27446911/#&gid=article-figur...

That record progressed

  2008 18.58
  2015 15.71 

2.87 seconds over 7 years. https://en.wikipedia.org/wiki/Kenichi_Ito_(athlete)

If we check in on more recent progress since then, we find the current record is 15.66 set in 2022. https://web.archive.org/web/20241222175947/https://www.guinn...

Another 7 years, for an improvement of 0.05 seconds, or about 850 years of linear improvement to reach Bolt's 9.58 seconds.

Anyone wanting to bet on beating Bolt by 2048?