There may also be some survivorship bias when it comes to the colonies. First colonies often failed and for quite a while (e.g. Roanoke nearly 100 years after Columbus), so I doubt it was all fun and paradise.
There are many places un-explored on Mars that will indeed provide a beauty unlike anything on Earth. This is an assumed fact, but it is mathematically just as likely to be true as the decision made that Mars sucks, based on current data.
We get there. We explore every bit of it. We find parts of it we can actually live on, quite comfortably - albeit, yes, still in a tank. But there could be parts of Mars we can transform, within a 100 years or so - just like the early settlers of every continent on Earth, ever in the history of mankind - and turn into a habitable place to live.
All it takes is one Martian generation, or two, and maybe there will be Martian-humans who have the conversation "I could never live on Earth, far too strange and unknown .."
We evolved to be interested in the things that keep us alive or can kill us - other flora and fauna and water are the top of that list. We find variations of that endlessly interesting. Rock formations, not so much.
Man wants to conquer Mars but I don't to see the pitiful existence of those poor few fools who sacrifice themselves for our collective egos. Especially the first settlers who can't come back and beg for their lives over the video link constantly.
It doesn't make a lot of sense to jump out of this deep gravity well just to be stuck on another one at our current technology levels. Instead asteroids will be much more inviting and the technology to harvest them will combat the large existential risk from rogue asteroids that is one of main arguments for the colonisation of other planets in the first place.
Mars' atmospheric pressure is 0.6% of Earth's. It's for all practical purposes a vaccum. Liquids boil away. You will die without some kind of suit even if you converted all the gases to nitrogen and oxygen.
Mars has 10% of the mass of Earth. Surface gravity is a third of Earth's. Long-term survival in low-gravity might be possible, but it will not be pleasant and it will mean returning to Earth will be effectively impossible.
Mars will never be habitable unless we assemble a whole new planet.
I can imagine a several large domes to protect people and crops from the atmosphere, but the threat of them being hit by a meteorite seems like a critical issue, unless we also shipped some AA or powerful lasers to combat them.