there's places on our own planet that we can't colonize with current technology, and they don't even have problems with air/radiation
Sure, but breh said we'll
never colonise Mars.
Barring a catastrophic species ending event colonising Mars is obviously inevitable. The question is just when. This century? Next millennium? In 10,000 years?
Assuming humans don't have any catastrophic event, I don't think in say, 1.2 million years we will still be wondering when colonising Mars will be a reality.

. Or 120,000 ears or even 12,000 years, given the insanely rapid growth of technology and the current exponential growth of computing power.