The reason for Delphis lack of popularity now is because the era of the desktop application died around 2012 or so.
Everything is a webpage now, including many mobile apps. The cost we have paid by using HTML and JS as the way to build apps is not well recognized - everyone only does it because there is no real alternative. The Stockholm syndrome is fully matured.
React/Angular etc are the equivalent of what the VCL was to the crude Win32 API and MFC base. React is as close to RAD as you can get without a visual designer.
If I was going to develop mobile apps that were much more than a CRUD like UI, I'd probably opt for Delphi