I think this is where standardized DSLs are needed in order to make software an effective and useful tool for nonspecialists. Doing everything in a full-featured programming language is like bringing a fully-loaded aircraft carrier to what is, in most cases, a pocketknife fight. If you only provide a pocketknife, you don't have to worry about accidentally burning down the entire city.

Besides, standardized DSLs are often better suited for static analysis due to the restricted forms of control flow and less esoteric constructions (fewer or no pointers, dynamic allocation, etc).

If only vendors didn't force users into closed, proprietary IDEs which lack many basic syntactic checks, developing for industrial control system would be much more pleasant.

But there is absolutely nothing in the manufacturing world that would ever require millions of lines of code. There's a big difference between software development, which they are not doing, and coding, which these no-code solutions seek to help them with.

For reference, I'm currently dealing with a customer whose most complex machine (which automates a job that used to take two people per shift) runs on 128 lines of code.

The problem is many of them think that they can handle larger problems

Let them think that. As the GP poster said, it is unlikely they will ever be asked to work on a bigger program.