This discussion about the code editing (and gutenberg in many ways) boils down to wordpress just not wanting to grow up and be a CMS used by professionals, and it prefers to be more of a fronpage/dreamweaver clone :(

Can anyone imagine a webmaster of a portal just decide to "fix" something in WC code and just goes and does it?

And the "admin can do everything in any case" argument is just not realistic. I heard of at least one site in which there are more than 20 admins, and as long as wordpress to not force the separation of admin role from authoring related roles, I can see this practice continuing since obviously it is easier to give admin right to people than putting effort into properly configuring capabilities.