Linen and hemp are long staple fibres, that means that they are betwwen 25 and 150cms long, cotton for comparison is considered long staple if it's over 25mm.
Modern spinning prefers short lengths, and it uses up the short broken lengths that traditionally were only used for coarse fabrics. The short broken lengths are called tow. (that's the origin of the phrase tow rag, not something that cleans feet, but a kind of hairy looking scrap of cloth. )
To use all the fibres modern machinery cuts the flax and hemp into short lengths before it's spun.
This means that modern linen and hemp is not as long lasting or hard wearing as the older fabrics.
Most folks don't care, it's still linen and hemp.
Hemp is a beautiful cloth, is more easily grown, and more productively, than linen, and has none of the pesticide and water issues that cotton growing has. Better all round; ah but, it used to have those pesky canabinoids in it's leaves.
Basically this is an American pre and post WW2 issue that spilled over into Europe.
They had a huge opprobium about cannabis smoking (calls for sterilisation of those who smoked it, huge health scares, etc.,) and banned growing hemp because of it.
Sheer stupidity since the stuff that produces the best fibre doesn't produce the high

especially with modern farming seed selection.
Not all of Europe fell into line however, and some of the most beautiful home grown, hand spun and woven hemp I have ever seen comes from Hungary/ Romania. They spin and weave in three qualities, and the finest is as fine as lawn. I have seen it woven to 30 to 35 threads per cm. Absolutely excellent
Machine made stuff by comparison is crude.
Hemp is generally a little softer in wear than linen is to begin with. It has a slightly different handle, even when it's a thick cloth.
Choice ? Either / or.
Tbh they are both excellent, they are best worn and washed, worn and washed. This creates tiny micro fractures along the fibres that eases the creasing that both are inclined to when new.
Both last very, very well indeed. We have line cloth that's several thousand years old and it's still sound.
Environmentally hemp wins
cheers,
Toddy