"It's possible" is a rather low bar. It's also "possible" in C. Is it easy though? I wouldn't say so. Not if you push lambdas over queues to be invoked in another thread, or in the same thread, but later. Not if you take references to elements of std::vector. Not if you use std::vector<bool>. Not if you use operator[] on std::vector/std::array without tweaking some macros, because C++ committee in 2021 is still not convinced that bounds-checking is a reasonable default.

It's very easy on the other hand to write perfectly idiomatic "modern C++" which is memory-unsafe. Well... Easy if you figure out which one, among a dozen, is the right way™ to initialize a variable. (And then go and read code which initializes std::vector in all those different ways and try to guess which one does what.)