Comment by pjmlp

Visual Basic 6 was quite limited, it was a programming language designed for doing applications.

Delphi, with its Object Pascal roots, was(is) a systems programming language that also happens to have a nice RAD tooling for GUI applications.

Put in another way, it didn't own anything to C++ in capabilities, and had VB like tooling.

VB had to wait for version 6 to support AOT compilation and being able to implement its own COM based controls without depending on C++, and even then it only supported a subset of COM features.

Meanwhile the GUI framework being used by C++ Builder is actually written in Delphi.