Computer? Cadence Sensor? Power meter? Are they worth it?

[EckyH]

In the early days I spent almost as much time looking at the screen as I did the road ahead but these days I go miles without looking at it.

Same here.
Even on the old Garmin 800 I can choose which data is where on display. When I'm on my commute then I have the current time on top, then the distance to have an indication when to take a sip to stay hydrated, followed by (one font size smaller) the actual speed as an indication for cadence, battery level and lap distance.

When I ride along a route then mostly just the route is on the display.

E.