The grandparent is talking about Venus atmosphere.

It seems the conditions in the upper atmosphere of Venus are acceptable. If you can manage living in floating cities (that it's cool but makes it a very difficult endeavour) then, Venus is close to Earth than Mars and the gravity is similar to the one in Earth.

As always, Wikipedia have this covered: https://en.wikipedia.org/wiki/Colonization_of_Venus#Aerostat...

PS: I'm upvoting the GP, by the way. Why people downvote instead of asking for clarification.

The GP was mostly downvoted because of the unnecessarily supercilious tone. Instead of explaining why they thought Venus was better for this purpose, GP just chose to end with a haughty-sounding "I don't think they have thought this through." Considering GP is a random stranger on the internet, and "they" is SpaceX/Elon, the downvoting is natural.

Maybe. But I think that it's, precisely, because we are random strangers in the Internet and we all know how easy is to misunderstand intentions by text, that we should think two times before downvoting.

It's my personal opinion that downvoting is used too easily in HN.

Sometimes it seems that we are trying to filter opinions that we don't agree with, instead of policing good manners and filter irrelevant to the subject comments.

It turns out that that the atmospheric mix of Earth's surface (of N₂ and O₂) would naturally settle at the atmospheric column very near where the temperature is pleasant by Earth standards. Such floating colonies would basically be completely palatable by Earth standsrds (albeit perhaps with temperatures more reminiscent of Australian outback or Qatar than those of Europe or the US).

Floating colonies present their own issues, but it would solve concerns about long-term low-gravity impacts of Mars or the challenges of requiring a fully-pressurized environment suit all the time outdoors.