Website https://control-webpanel.com running very slow?

Why the main website https://control-webpanel.com is running very slow?
Very difficult to access this website, sometimes I have to refresh it many times, and most of them I just stuck at "CWP Logo" with white background forever. 

All of their infrastructure feels very slow -- including this Forum subdomain. I used to think it was my paltry DSL connection, but not that I am on fiber and have a general feel for how my service loads content -- CWP's sites are objectively much slower to load than other web content, including "pig" sites like Facebook.