Exactly. There is a lot happening implicitly in a C program that the programmer has to be aware of and keep in mind. And it’s made worse by valid compile implementation choices. I remember chasing a bug for a day that was based on me forgetting that the particular implementation I was working with had signed characters and was sign extending something at an inopportune time.

C is simple like SMTP.

As someone who has had to parse C syntax for a living, I'd argue that it's not syntactically simple either. (Declarators are particularly nasty in C and even more so in C++).

Entirely my point. Simpler in some ways, more difficult in others. Totally depends on the use case