“ The Object Pascal ecosystem has two options: Embarcadero Delphi (proprietary, Windows-first) and Free Pascal…”

This part isn’t true, for many years now we’ve also had Oxygene - https://www.remobjects.com/elements/oxygene/ (also proprietary)

Which has had a strange relationship with Delphi, for a while they were responsible for Delphi.NET.