So much of C++'s value proposition is based off the fact that it has such strong legacy compatibility. It's a language that is used today by businesses who are

So much of C++'s value proposition is based off the fact that it has such strong legacy compatibility. It's a language that is used today by businesses who are risk averse. Deprecating parts of the standard will make C++ a much less attractive language for the people who make up the majority of it's current user base. You also can't deprecate anything required for C interop, like the preprocessor.