Trans girls sometimes minimize the bulge that having a penis causes to be visible through clothing by tucking and securing their penis so that it’s less visible. Some trans girls don’t do this because they find it inconvenient, unpleasant, or just don’t feel the need to do so. Packing is typically done by trans men, it’s when you have a packer to give the appearance of having a penis; it’s usually a soft silicone penis and balls of varying levels of realistic appearance. The joke is that the tuck/don’t tuck trans girls are terrified of the trans girl who wants to make it look like her penis is even bigger.

I’m not sure I would classify anything I wrote as wisdom, but the OP did make me giggle