There are many reasons why a website can be slow. The connection can be slow, the code can be slow, the database or queries on the database can be slow. And all of those things are probably different on our servers than they are on your own computer.
And also they won’t increase performance for your site over anyone else’s, they like to keep it fair and even for every user.
I tried with just one page (just HTML) and same problem : the website are very very slow.
Actually, on the website, i use Joomla.
I also tried with an other PC, an other internet connection, and with a smartphone 4G, the website are again very slow.
It’s depend to the connection time : In French Hours, if i try to go on my website between 4 and 10 PM, the website are slow.
Also, i tried to use other PC, other connexion internet with fiber, smartphone with 4G, same problem.