The 1500m GOAT? Not sure about that. It would still not be the equal of Coe's back to back golds, as Jakob had the fortune of the 2020 Olympics being delayed to 2021. He would not have beaten Tim in 2020, and he has just a 3 year gap between Olympics.
He has also lost to Jake Wightman in a major championship, and nobody thinks Wightman is yet the equal of Coe (still possible that could change if HE wins Olympic Gold, as well as defending his crown in Budapest).
Jakob has still not run as fast as Coe (or Cram) by any reasonable estimation of the time benefits of super shoes and the latest Mondo tracks. He still could become the 1500 GOAT (although some would still say he has to beat El G's doped WRs), and indeed the GOAT runner, but probably has to do more than 'simply' defend his 1500m Olympic title.