These German officials are wrong on multiple levels, not least of which is a fixation on current testosterone.
Blood-serum hormone levels are a red herring, and do NOTHING to ameliorate permanent advantages such as bone length, muscle-mass percentages, larger heart and lungs, etcetera.
David J Handelsman, Angelica L Hirschberg, Stephane Bermon, Circulating Testosterone as the Hormonal Basis of Sex Differences in Athletic Performance, Endocrine Reviews, Volume 39, Issue 5, October 2018, Pages 803โ829,
doi.org/10.1210/er.2018-0002โฆ.
If I can reduce my hormone levels to that of a ten-year-old, should I be allowed to compete against grade-school children? Of course not!