In C++ you can trivially opt out of using a dynamic array.
There are plenty of reasons not to use C++, including the lack of memory safety, but if you've already decided to ditch that, C++ does let you pick and choose which parts you want to use.
Not to the extent of C++. E.g. you can't opt out of dynamic dispatch overhead in Ruby, because everything is method passing, but "virtual" in C++ is a choice.
The commitment to ensure that features do not add cost(memory, runtime) if you don't use them is something fairly uncommon in other languages, and many languages have features you can't meaningfully avoid.
There are plenty of reasons not to use C++, including the lack of memory safety, but if you've already decided to ditch that, C++ does let you pick and choose which parts you want to use.