That's an interesting set of observations Doug and Nagol.
Personally I think it is based on the following technique(s) of displaying magic as a game concept in D&D. With artifacts and relics and so forth you have so many different kinds of magical effects that can be displayed that one has a hard time "guessing or knowing" what effect the item will manifest next.
That is to say high level magic items have a wide option choice of magical effects and displays, which adds to the mystery of the manifestation. It is not a simple one lever-one effect operation.
Simple magical items, +1 swords and so forth, can't project that element of "the unknown or mysterious." Not with that system anyway. It's like you say, low magic is a simple mechanical or technological operation. It only usually does one simple thing, like an extremely simple machine.
I think you can change that by making low level magical items fluctuate in what they do, or by changing the way they "present helves" on occasion. They would still do mild things, by comparison to high level magic, but only one thing at a time, yet also various or changing things.
But I think you made a good observation and I like the idea of the paradox of magical-technology in D&D. I think it can be fixed, or at least changed, but I like the point.
The difficult part is balancing useful reliability with unpredictability.
The character and/or the player not being capable of predicting what the magic item will do next severely reduces the player's incentive to use the tool. Reliability and predictability is highly sought after in tools that you are relying upon for success (and in the character's case for survival).
The Wand of Wonder is the archtypal unpredictable magic item. Many players will pass on its acquisition. Many others will only use it when either (a) success is all but certain or (b) defeat is almost certain otherwise. Very few individuals in my experience pull it out as a tool of choice when they think the outcome is tight, but winnable. The reason for that is simple: the item is too unpredictable to be relied upon. Wild Magic has gone through a lot of revisions/publications of possible results because the unpredicatablility one group appreciates is unacceptable to another.
Adding an item that shifts between known states adds uncertainty for the player at the cost of complexity of tracking for the DM. The player's state only lasts until he works out the pattern for shifting. At that point, it adds some complexity to the player to work out when/how to shift the item to achieve the desired result. Alternatively, the player doesn't take the item into consideration and only takes advantage of it when it coincidentally offers the effects desired at the time of need.