I agree that most people don't look at who the SSL cert provider is, just that the site is https:// with the green padlock. Having a more robust SSL cert that lights up the address bar is a nice to have but certainly not a must have. The only must have is a basic SSL cert mainly because of the "This site isn't secure" warning messages web browsers like Chrome throws at people when they go to fill out a contact form, mailing list form, etc. They've made some kind of SSL cert on your site basically essential even if it's free from Let's Encrypt.