Our wholesale Shopify apps' script is loaded asynchronously. It neither slows down the page nor affects the loading of other apps. But the app can't be fully loaded until the whole page is loaded. So if you have a lot of apps or content on your product page, there may be some delay before the form is fully loaded. And we can't change it, really sorry.
As for the Wholesale pages, the delay may occur if there are a lot of collections added to the page so the time is required to upload all products and variants.