The issue is that people are confusing semantic marking with display presentation.

Markup (and markdown) constructs are for indicating semantic types like emphasis using *asterisks* and strong emphasis using **double asterisks**. The presentation of those styles as italic and bold is a style question. Except for HTML's poor support for underlines, I suppose we could have just as easily chosen u̲n̲d̲e̲r̲l̲i̲n̲e̲ for the display of emphasis. Likewise, SE could switch all italics with bolds and it should have no effect whatsoever on the meaning of anyone's content.

The backtick is just another one of these semantic markers, a "code" or "literal" type. But part of its semantics is the implication that markdown is literalized, <em>like here</em>. On a coding-oriented forums the code type is displayed as highlighted monospace because that's useful to coders. On an English-language-oriented forum code could be displayed as bold italic or whatever is useful to that community. But it would still have to support literalization/escape of markdown characters inside code blocks.

However, one real issue is that people use the code type for non-semantic reasons; i.e., they are trying to control how their content is displayed -- taking advantage of the monospace or highlight to simulate tables, for example. People shouldn't have been doing this, but SE really offers no alternative. Changing code will break all these. Not saying that's bad, though.

The issue is that people are confusing semantic marking with display presentation.

Markup (and markdown) constructs are for indicating semantic types like emphasis using *asterisks* and strong emphasis using **double asterisks**. The presentation of those styles as italic and bold is a style question. Except for HTML SE's poor support for underlines, I suppose we could have just as easily chosen u̲n̲d̲e̲r̲l̲i̲n̲e̲ for the display of emphasis. Likewise, SE could switch all italics with bolds and it should have no effect whatsoever on the meaning of anyone's content.

The backtick is just another one of these semantic markers, a "code" or "literal" type. But part of its semantics is the implication that markdown is literalized, <em>like here</em>. On a coding-oriented forums the code type is displayed as highlighted monospace because that's useful to coders. On an English-language-oriented forum code could be displayed as bold italic or whatever is useful to that community. But it would still have to support literalization/escape of markdown characters inside code blocks.

However, one real issue is that people use the code type for non-semantic reasons; i.e., they are trying to control how their content is displayed -- taking advantage of the monospace or highlight to simulate tables, for example. People shouldn't have been doing this, but SE really offers no alternative. Changing code will break all these. Not saying that's bad, though.