Hi Andreas,
To eliminate the odds, can you exercise iperf between your windows 2022 server and V3000 (which I believe you have configured as POP) and see whether 10Gbit switch is contributing this behavior.
example iperf cmd on your 2022 server
iperf3 --server -p 6004
example iperf cmd on CLISH of V3000
service iperf -c -t 10 -p 6004
more references: Link Test using IPERF in CLISH
I am about to make observations related to your painpoint on 1.2.2.1-b2.
Shall keep you posted