Europe can ban GM soybeans, because there is a ready supply of non GM soybeans, enough to meet their needs. Brazil has boosted soybean production dramatically over the last decade, and can supply those needs.
But, if we look a bit deeper, there is a problem with this.
Soybeans are a very high protein plant. Consequently, they tend to draw out a lot of minerals from the soil, more than just about any crop. In more developed agriculture, such as in the US, this problem is addressed by rotating crops: soybeans grown for one year, with grasses for the next two years to replenish the minerals in the soil, so that the land doesn't become barren.
In Brazil, they don't do this. As this article illustrates, Brazilian farmers simply grow soybeans until the soil is exhausted, and then flatten more rain forests to get more fresh soil. Of course, when soybeans have exhausted the minerals in the soil, not a lot else will grow there for quite some time. But, since Brazil has more land than hard currency, it's cheaper to just destroy more rain forest than replenish the land that has already been cleared.
In addition, the soybeans grown in the US have been modified to boost their defenses against weeds and insects. This isn't 'frankenplant', it is simply increasing the plant's production of substances they were already producing, that keep insects and weeds away from the plant. Many plants do this... walnut trees produce a toxic sap (that also produces their bitter smell) to keep other plants and insects away.
Consequently, the non modified soybeans require much higher levels of insecticides and herbicides to keep the soy plants from being overwhelmed by weeds and insects. Due to the nature of the soy plant, which tends to spread out across the ground rather than grow upright, weeds can't be controlled by cultivation... which would destroy the soy plant as well.
All crops grown for food today are genetically modified from their original form. What we're quibbling over is whether that modification is done in the lab or by selective breeding.
So in this case, Europe has simply shifted soybean farming to a much more destructive form. It appears that their social conscience may not extend beyond their own borders.