If you're willing to give Emacs another shot, check out LSP-mode [0]. It's an implementation of the language server protocol, the same tech that powers the autocomplete/jump-to-def/etc. in VS Code, and so it offers exactly the same functionality for all the same languages. It's true that it's not built into Emacs, but it's easy to set up and works well.

It's been a total game changer for me - it's allowed me to transition to using Emacs full-time for professional Python programming.

[0] https://github.com/emacs-lsp/lsp-mode