You are not alone when you ask this question yourself. If you go to various web designing and development forums filled with tech people in it, there is a high possibility that you will get laughed at for using a WYSIWYG editor in order to create a website. There will be others that will recommend you to use the editor though if your purpose does not require the in-depth knowledge of HTML and web development. But the question remains whether it is better to use the WYSIWYG editor or learn HTML.
The adherents of hard coding have a lot to say to you if you tell them that you prefer to use WYSIWYG editor. Forget about asking them and focus on the purpose why you want to create a website in the first place. Generally, for those who are webmasters by a certain incident, they do not really need to learn HTML that deeply, particularly if you are going to make a website as a means to an end. For example, you want to create a personal blog about your adventures or a website to sell your products and services, etc. If you fall under this category, it will be overkill for you to learn about in depth web development. The use of visual web editors, also referred to as the WYSIWYG, users are given the ability to freely design a web page easily and that it does not require any prior knowledge about HTML and CSS. As you design them through the editor, it will generate codes according to those elements you have placed.
But if you are still fighting a battle whether it is better to learn HTML or not, this could be due to the reasons that some people have said to you or what you have read over the internet. Learning HTML would have been valid during 90s when the internet was still new and growing. However, in these times when everything is getting too fast, there is a need to use the editor to shorten that time. You will be shocked to know that there are a number of professional web developers and designers that use both tools to achieve the purpose of their website, even if it is different from the reasons stated above. Learning HTML and many other web development languages is better off for those who make dynamic websites that involves a lot of functionality, such as placing a database that handles saving passwords and creating accounts.
The web designers and developers of www.paperbackwebsitedesign.co.uk utilises both because they find it more convenient that way, but they might give more time working with the WYSIWYG editor rather than with hard coding, because it gives them the convenience of saving time and putting more of those extra time into developing the website more, especially when the editor does not give the right kind of formula that web designers and developers seek. Whether your learn HTML or use the WYSIWYG editor for website design and development is all up to you.