I think a lot of developers are wary of building on shifting sands. Once bitten, twice shy. The project is unreliable in that new surprises and demands are made on site creators with every release.

An example situation: A client wants me to specify a corporate site for them, it is to be edited and maintained by their interns. I must cost it and give a timeline, and provide training docs on how to edit (at a level an unskilled new employee might understand)

How do I prevent the editors from adding weird backgrounds, filtered pictures, etc! I lock it down, I must include my boilerplate which locks and hides the effects, most of the blocks, the WP pattern library, the patterns (because the implementation changes so often its a massive workload to support), and as for FSE … no client wants this, so now I have 80 more things to try and discover the way to turn them off.

So that’s corporate clients, but what about small business , one person selling from home and maintaining their own site?

In my experience with those clients they start off excited to drag and drop a site design, tantalised by ads and chafed by the cost of hiring a webdev. These sites end up a total mess and I’m asked to “make it really simple, just get rid of everything, just make it black and white”.

Because these single traders are not designers, and do not have the time or inclination to learn about layout, colour theory, never mind about topics such as SEO.

The developers of WP gutenberg and FSE are working hard, but I cant see the benefits to any client. And if I develop for it then the burden is on me to support clients in every change to the implementation.