There is a chart here from the same site (which would have been useful for them to have included in the main article) which shows how this device theoretically compares with others and with the end goal:
Why is it unclear? AFAICT, it lies outside the shaded region (just below the bottom left part). The scale is in the chart is a little unclear, but all the data is in the article.
https://www.ipp.mpg.de/15144/zuendbedingungen
Unclear where in that shaded region the new result lies.