I see no reason why he shouldn't express his opinion on the committee's goals re backward computability.
Defending the status quo by saying "well duh, you should know better, take it or leave it" is just a way of rejecting someone's contentions without actually addressing them. In a reasoned debate that's indefensible.
If he's wrong, tell him why rather than telling him to take his ball and go home.
Existing code is important, existing implementations are not. A large body of C code exists
of considerable commercial value. Every attempt has been made to ensure that the bulk of this
code will be acceptable to any implementation conforming to the Standard. The C89 Committee
20 did not want to force most programmers to modify their C programs just to have them accepted
by a conforming translator.
Note that this guiding principle was listed first. The author disagrees with one of their fundamental guiding principles. My point is that he then has a fundamental disagreement with the purpose of the standard, and for that reason, perhaps he is using the wrong tool.
If someone has the guiding principle X, and someone else has the guiding principle !X, I contend that difference is irreconcilable.
Dennis Ritchie, C's creator, along with Ken Thompson, Unix' creator, and other Bell Labs people from the Computing Science Research Center thought the C standardization committee was wrong, so the Plan9 C compiler[1,2] is not ANSI compatible. Not only the standard library is nothing alike, the language itself is slightly changed in an incompatible way.
