When the pilgrims originally sailed to North America from England, it took on the order of two or three months. A six month trip to Mars seems reasonable in that context.
The pilgrims didn't have to worry about being subjected to deadly cosmic radiation. They could also bring various tools with them and build habitats in their new home using readily-available materials, and grow food there from seeds (though they should have picked a more southerly landing spot...). They also didn't have to worry about having pressurized environmental suits just to walk around outside once they made landfall.
No, they just had to worry about weird diseases, storms destroying their boat en-route, not having any clue where they'd land or what the territory would be like, and being attacked and killed by angry natives. Oh and they were doing it all with pretty basic "science".
None of those problems exist on Mars. Others exist, but you can't just directly say it was easier.
