Say the springs compressed 10mm for every 25mm of wheel travel and that there is 100mm of wheel travel up to hit bump stops when at std height. That means the spring would compress 40mm at std height or 60mm on 50mm lift before hitting bump stops. 60/40 = 1.5 or 50% more force (or weight) to hit bump stops with the same rate spring which of course would have to be longer to provide the lift. You would need a spring 1/3rd lighter to get the same amount of suspension travel. Probably very nice for rock hopping but not suitable for road travel.
You are missing my point
" 1/3rd lighter springs to get the same travel "
it's the same travel
So it's takes more force That's a given, how do you know that is an issue for limiting the travel, get the correct spring go 4wding it will hit the bump stop without any issues