Having the same issues in Belgium. I’ve tested several different DNS settings (own unbound DNS server, 1.1.1.1, 9.9.9.9) but without success. No IPv6 on my network.
Roon core is running on a VM (Intel i5-10400, 4 cores, 8GB, latest Debian) but I’m experiencing the same issues when running on my desktop (i7 8700k, 16GB, Win 10 21H1)
Speedtest gives my around 270/19.
Using Qobuz for streaming.
I’ve posted in another thread too: Slow loading of Artist Overview and Information - #10 by Christophe_Saelens