That does not has to be! If you are willing to learn CW, you can cover the entire world with a full HF station that is easily less than 1 kg including pole and antenna.
See this link:
My current station is
A MTR 3 B in a “TinySOTA” enclosure including battery for >2h operation, SWR meter, USB charger, etc. - less than 350 g including earphones and rugged case.
An endfed or vertical wire antenna - 100 - 200 g
A carbon-fiber mast 5 - 6m, starting with less than 200g.
Here are pictures of the station:
Of course, you do not have take the effort of building a similar station - an MTR as off-the-shelf from LNR will go a long way. And SOTA DX contacts are well possible even at this point of the solar cycle.
73 de Martin, DK3IT
Edit: One more thing: 5 W QRP is really plenty for SOTA HF. No need to carry a 100W beast up on the summit.