there is nothing special about negative voltages, it's all relative to some point anyway.
With mixed analog/digital circuits for example, it's pretty common to treat exactly same voltages either as -2.5/0/2.5 (relative to midpoint), or as 0/2.5/5 (relative to negative rail).
What matters is having multiple treshold voltages with distinct behaviour. Setun used ferrite transformers which do have multiple thresholds (postive and negative fields) - but modern electronics, including transistors, does not.
This is 1000% not my area of expertise, but if we're imagining circuits where current can flow in different directions at different times, would diodes potentially become more interesting for logic?
Diodes have quite big forward voltage, like 0.5V, depends on current but in any case it means lots of wasted energy. FETs got highly optimized over time, can be switched on with only minuscule resistance and also can be miniaturized.
Modern FETs are capable of switching spot welding currents without getting destroyed, while in thumbnail-sized package, imagine that. My grandpa was an electrical engineer and would be completely blown away by such a component.
DTL, diode-transisor logic, was used in 1960-1970's when they did not have cheap high-quality transistors yet. The power consumption was pretty terrible, but you needed less semiconductors.
In the modern logic, diodes are not that useful because transistors already react to one polarity only. You simply connect multiple transistors to same input, and the right ones will activate.
With mixed analog/digital circuits for example, it's pretty common to treat exactly same voltages either as -2.5/0/2.5 (relative to midpoint), or as 0/2.5/5 (relative to negative rail).
What matters is having multiple treshold voltages with distinct behaviour. Setun used ferrite transformers which do have multiple thresholds (postive and negative fields) - but modern electronics, including transistors, does not.