Yes, that's the point. For everything outside the box you need to install a Plugin for IntelliJ too. So there is no difference in that regard.

But there is a difference in culture and availability between a box-driven community and a plugin-driven community. The plugin-culture has more likely a good plugin for something exotic than the box-culture.

For example, searching for mermaid (popular diagram-tool for markdown) in InteliJ-Plugins I only found one commecial plugin that I need to pay for. So it seems here already is a popular corner which is not well covered in this box-culture. And we always can go deeper there, toward more exotic stuff.

For VS Code I immidiatly found a dozen tools BTW.