Hi,
The theme has been on Themeforest for a long time, which means it has passed all the quality censorship of Themeforest. And, of course, includes site loading speed.
Load speed depends on many different factors. For example, network speed, hosting/server, third-party plugins, or image size is too large,...
So I think, in this case, you should check again your hosting. You can ask for the hosting manager to get the information. Then pls let me know.
You also can install the plugin about Cache to improve this situation
Regards,
Yame