Bioengineered means a specific thing in this context. I dont like using the term "genetically modified" because, well, everything is genetically modified, thats how agriculture works. Bioengineering narrows down what's being discussed to genetic modifications using synthetic biology tools from the field of bioengineering. Even more specific would be to say they aren't transgenic plants. Were getting to the weird point now where you can use synthetic biological tools like crisper to change the DNA sequence of a plant, but because you aren't introducing a new genetic sequence, the resulting plant isn't considered a "GMO" because the legal definition is more concerned about transgenic sequences than the use of bioengineering tools. These are all just really vague and highly politicized terms.