Humans were terribly designed to cross the Atlantic by swimming as well, but we designed boats so eventually we did.
Yes, robots are a cheaper and more reliable way to explore and extract resources but I doubt mankind will be happy with just that. We like to explore, and expand, and face challenges so I'd bet that no matter the setbacks or price tag, we will eventually prefer to do this things in person.
As an alternative: we could even redesign ourselves for space exploration if needed be.
As to your wider point, the ability to breath oxygen and have long term fat stores makes an Atlantic crossing very easy. We moved from one palace with humans to another place with humans, hardly a massive feat of engendering. Meanwhile people in far more primitive craft ended up living in Hawaii (2,200+ miles from the nearest land mass) of all palaces.
Astronauts have traveled further on the moon on the three missions that included the Lunar Roving Vehicle than all our mars rovers managed combined.
If you give a mars rover a command, it takes an average of 12 minutes for that command to reach mars, and another 12 minutes for the confirmation to come back. That makes remote control very hard, and we aren't all that good with autonomous robots.
So until we figure that whole artificial intelligence thing out humans are a much better bet for getting significant amounts of science and mining done than robots.
The rovers we've sent to Mars weren't designed to travel great distances. Autonomous rovers built for maximum travel distance would be pretty easy except for supplying them with enough energy and protecting their delicate parts from the elements. Both problems are harder for humans, even on a one-way mission.
What's wrong with low G tolerance for interstellar travel?
If speed of light is ~310^8, 1G ~ 10m/s^2, you would need (ignoring reletivistic effects) 310^7 seconds to reach the speed of light.
There are 86400 seconds in a day, so you would need ~347 days to reach the speed of light if you were accelerating at 1G, were it not for relativistic effects.
> iirc we don’t have “permanent” acceleration tech
Which is exactly why low G-tolerance doesn't matter. You have a limited amount of delta-V, whether you apply it all in one go or spread out over a year makes little difference given the timescales that are already involved in interstellar travel.
Humans may also be the best at handling what you stated. You’re comparing us to robots but if you say humans were designed then our collective knowledge limits us to 1 at present. So we’re the best and worst.
I always believed that if humanity is to colonize something, it would be through robots that do all the exploring and mining for us.