A young purple-leaf plum may leave plenty of space beside a path while still growing into a position that will be awkward later. Check the named tree's expected size before treating regular hard pruning as the planting plan.
Consider branch height, canopy spread and access for maintenance. Also look at nearby windows, gates and other plants rather than judging the spot as an empty circle of soil.
Shape with a purpose
For an existing tree, identify the branches creating the problem and seek pruning guidance appropriate to the tree, the cuts required and local conditions. Removing the same amount from every branch is not a substitute for understanding its framework.
Keep photographs from the path and from farther away. The view from directly beneath the tree can conceal how it affects the rest of the space.
If planting a new specimen, record its cultivar and mature dimensions in the garden plan. A smaller suitable tree may be easier to live with than a larger one expected to stay small indefinitely. Choose the plant and position together, while the decision can still be changed without major work.
The NC Extension purple-leaf plum profile describes a spreading crown and distinguishes named cultivars. Use the expected dimensions of the actual selection when planning path clearance, rather than assuming every purple-leaved plum will remain nursery-sized.
Related reading: Purple-Leaf Plum Care: Planting, Watering and Pruning.