I don't think anyone is suggesting shared_ptr explicitly, more that if you're coming from Python/Java/etc it's a similar to a GC memory model and a bit more familiar if that's where your experience is. I've observed in a number of codebases unless you're setting a standard of unique_ptr by default it's fairly easy for shared_ptr to become widely used.

FWIW I consider shared_ptr a bit of a code-smell that you don't have your ownership model well understood, there are cases to use it but 90% of the time you can eliminate it with a more explicit design(and avoid chances of leaks + penalties from atomics).