I was not aware of this fact, having seen many crucifixes complete with the figure of Christ in Anglican churches. But if I may hazard a speculative explanation, it is this. The figure of Christ is removed from the cross because of the strong ideological intolerance felt by certain Protestant denominations for religious icons and images. The early Reformers of the Protestant Reformation, in their zeal to find fault with and distance themselves from the (Catholic) Church of the time, decided that the use of icons, that is figurative representations of holy persons or biblical scenes, in churches was somehow not in accordance with the Old Testament prohibition of the worship of graven images as enunciated in the Ten Commandments. This was in part motivated by a justified disapproval of clerical abuses such as the sale of religious relics to raise revenue for the Church. As a result, rabbles radicalised by the more fanatical Reformers went on destructive rampages attacking iconic works of art in Christian churches and monasteries, which as a result of the Protestant ideological shift they no longer considered pious aids to prayer but worthless symbols of superstition. In England this shameful episode of religious intolerance was dubbed the Dissolution of the Monasteries. There are many instances of religious statues that were decapitated or otherwise vandalised, if not stolen or entirely destroyed. The sheer brutality of these acts of religious vandalism is comparable to that of the Muslims that destroyed the priceless residual collection of manuscripts in the Great Library of Alexandria upon capturing the city, because they deemed them not to be in accordance with the Koran, and therefore worthless (to them); and to that wreaked by the (Christian) Crusaders in the Sack of Constantinople.
There is of course a significant difference between a graven image that is worshipped as if it itself were one of a number of earthly Gods, thereby deflecting attention from the ineffable One God in Heaven, and an icon that is merely a representation of the Son or a saint or prophet of the One God. After all, a verbal description of the same is also a representation made by humans for the benefit of humans. The whole issue of the religious legitimacy of icons had been fiercely contested in the early church, and it was decided at the Second Council of Nicaea that the use of icons as aids to worship was legitimate and not at variance with the Old Testament prohibition of the worship of graven images.