Generally, this is a problem with tree cuttings propagation, including air layerring, not suited to most trees if you expect a full tree form. Major problems include sluggish branching and growth and poor anchorage. It is best to grow seedling and graft unto it. Seedlings have very good anchorage and well defined root system that can support vigorous growth.
But sometimes, it also depends on the cultivar. Lisbons on the other hand would always push out and tend to grow to a tree like form. It has vigorous adventitious roots that helps a lot. Some apples for example would have strong roots even if propagated via cuttings. Even some plum rootstocks are also propagated by cuttings and yet we get very good trees from them, same with other citrus rootstocks.
Take into account also the objectives of other home growers. Some of them would want their trees to grow bushy and slow growth but still productive, and this is an instance where trees propagated by cuttings would fit the bill.