Part of an event called Sternfahrt where cyclists protest for policy changes by taking over the city on 20 routes covering 2000 km of public roads.
some infos in german: https://berlin.adfc.de/pressemitteilung/adfc-sternfahrt-medienkit
translation to english: https://berlin-adfc-de.translate.goog/pressemitteilung/adfc-sternfahrt-medienkit?_x_tr_sl=de&_x_tr_tl=en&_x_tr_hl=en-US&_x_tr_pto=wapp
You don’t enter or exit at 120kph so throughput is cut by the bottle neck of exiting/entering (also the reason why there’s traffic no matter the number of lanes, bottleneck is the throughput of entry exit creates the traffic stall