Is there a way to access the menubar icons using the keyboard?
If you have "Use all F1, F2, etc. keys as standard function keys" checked in System Preferences → Keyboard → Keyboard tab

Ctrl + F8 moves the keyboard focus to the icons in the menubar

If you have "Use all F1, F2, etc. keys as standard function keys" unchecked in System Preferences → Keyboard → Keyboard tab

Ctrl + Fn + F8 moves the keyboard focus to the icons in the menubar

Although the leftmost user-installed ones on my computer cannot be accessed, you can then use the cursor keys to move ← → and ↓ to bring up the menu associated with the icon.

In addition, Ctrl + F2 (or Ctrl + Fn +F2) moves keyboard focus to the menubar items.