The GCC C++ parser is over a megabyte of ASCII text. Think about it: it takes over a million characters to figure out how to parse C++ code. This complexity is partially because there are so many ways to do the same thing.
All auto parameters, or make it a template? `if constexpr` or `std::enable_if_t`? Macros for generic programming or variadic variadic template templates? Overloading or specialization?
I love C++, and backwards compatibility is something that's been valuable for it, but it certainly comes with its challenges.
Firstly, nothing requires you to do things in a new way.
Secondly, if “you could already do that” implies “not really something new” for a programming language, updates to the syntax of programming languages can never count as “really something new”.
I think the issue he was speaking to was that if many of the new features require doing things in a new way then it really is something new. But your point is well taken as well. C++ is still C++ whether you use standard templates or not.