Why is wordpress (or any CMS) supposed to be "easier"???

Hi. About 15 years ago I got into some web design projects and I became reasonably comfortable with the technologies of the day. I haven’t done very much in the last five years and things have changed drastically, and I’m finding it a bit frustrating. As tends to happen, my knowledge and general feel for web design is frozen in the early 2000’s and today’s approach just doesn’t sit right with me.

I’m confused as to how CMS’s are supposed to be “easier to use” in any way, shape or form, compared with building a site from scratch (e.g. in dreamweaver) using HTML and CSS. I suppose the idea is that people with absolutely no technical knowledge whatsoever can install WP, pick a theme, and start “blogging” within minutes. But beyond this simplest of purposes, is it really any easier than just doing things, dare I say it, the old-fashioned way?

First and foremost, despite euphemistic claims of flexibility and complete control, one is of course firmly tied down when using any pre-built theme (for WP or any other CMS) and can make only the very slightest changes to the design and layout. I’ve been having a look at how to make your own theme from scratch and so far am finding it to be a rather perplexing process. Presumably I could pay someone to convert a HTML/CSS-based site into a WP theme for me, but then should I wish to actually change the layout in any way I would again be completely stuck.

The slight advantage to using a CMS is, I infer, that instead of opening your HTML editor and writing new content and uploading it, you log in to the CMS backend online, write new content, and submit it. I’m not sure if any time is actually saved by this method, for most purposes, when you factor in the much greater initial setup time and difficulty (assuming a custom theme and design, still).

The main advantage I can see is for systems such as online stores where regular changes in stock and news of proportions, etc., is made much easier than doing it all manually with dozens or hundreds of individual pages. BUT, the problem then is that you either have to have a separate “store” are that looks different to your main site, or accept that your business’s website is going to look like another tacky blog and probably be of an already-outdated style.

I think now I’m rambling like the confused old git that I am. Essentially I now need to create a website and am completely out of my depth in these supposedly “easier” methods of website creation. Am I mistaken to think that WP and its ilk are actually grossly restrictive in the availability and adjustment of designs, and that it would be far easier and faster to use clean and light HTML/CSS in most cases? Am I even more mistaken to assume that they’re supposed to be more flexible? Are they knowingly more restrictive in order to make it as easy as possible for people who can’t or won’t make their own designs?

The whole thing seems a bit like carrying a portable generator and your desktop computer with your shopping list on it when all you needed was a scrap of paper.

What’s the solution for me, here? I’m old and can’t learn new things as well as most of you, but I’d get my head around it eventually I suppose. Do I have to get on board the CMS bandwaggon or get completely left behind? Is there any place today for transparant human-readable websites based on just HTML and CSS?

Thanks!