The original statement, that the best computer is the one in your noggin is valid.
You get in the water with a plan.
The plan includes a gas usage plan, and a turn pressure.
You have a maximum depth, a maximum dive time. If it is a decompression dive, then the required stops.
In addition you have a just deeper, just longer and a longer/deeper plan. All within the available gas calculations.
Based on the plan, you can validate the data the computer is giving you. If you have just spent 70 minutes at 40 meters, and the computer says go straight to the surface, you can be pretty sure there is something wrong with the data you are getting from the computer. Especially, if the plan included staged decompression stops.
If your AI computer (or mechanical contents gauge) says you still have a full cylinder after 20minutes at 40m, there is something wrong with the instrumentation.
On every dive, engage brain !
Your point about adapting to new techniques and equipment is also valid. But, just because something is new, doesn't mean it is a good idea! Similarly, just because you can do something, doesn't mean you should!