There will be circumstances when wake turb cannot be avoided. Many incident encounters involve over reactions by crews. Modern autopilots are very capable for riding out attitude changes, but pilots must always expect the unexpected - keep calm don't over react.
I recall research from the 1970s - evaluating various sensors, which with other measurements identified a broad range of situations, e.g. arrival and takeoff spacing.
However, in many terminal manoeuvring areas there is insufficient airspace space for even the best detector to allow total avoidance; thus with track routing and spacing there can still be surprising encounters, but not the most intense. Thus crews must anticipate and manage.
En route, oceanic airspace etc, as discussed above; avoidance - never for certain, thus be prepared to be surprised.
Thoughts - ATC have predictive track collision avoidance; the converse, a view of past-track with descending wake might provide a means for alerting.
Similarly for ACAS; pilots should have a 3D mental plot of close traffic - what if.
'it's only a quick software change' patent applications via SP