Something I did for a client fixed on Godaddy was clone their site to AWS and another local host. Then ran speed tests in front of them. The difference was hug

Something I did for a client fixed on Godaddy was clone their site to AWS and another local host. Then ran speed tests in front of them. The difference was huge and they agreed to change. While its not strictly fair, it offered a clear & tangible difference to the client to help them make that leap.