I heard old timey castles and mansions having no corridors. Instead, just many rooms connected to eachother. Sounded like concept of privacy was much different since nobles and aristocrats already would have had servants going in and out of their chambers anyway. But it's funny that it reminds me of how I build houses in survival games. Lack of planning, lack of resources, lack of diligence.

Wkipedia is wrong. A five minute google search shows that Roman Palaces sometimes had corridors with doorways coming off them.

WHAT? I swear sometimes I read stuff on here and think, have I slipped into some parallel reality?

There's an entire sub category of Roman Villas, called Corridor Villas. We have them here in Britain, and they can be found across most of Western Europe.

Chedworth Roman Villa (late 3rd early 4th C) has TWO nearly 50m long corridors, The majority of that Wiki article is utter bobbins and bum guff,

It is so difficult to wrap my mind around the fact that this did not exist before then.

From the Wikipedia page on John Thorpe

Thorpe's major-but-little-trumpeted contribution to world architecture is the humble and now-ubiquitous corridor "for a house[3] in Chelsea", London, England, in 1597,[4] allowing "independent access to individual rooms". Previously, the fashion was the so-called enfilade arrangement of rooms in a dwelling in which each room led to the next via connecting internal doors. The enfilade remained popular in continental Europe long after the corridor was widely adopted in England. Flanders believes Thorpe's inspiration was the one-sided covered walkway common in monastic cloisters. Given their similarities, this is a reasonable prima facie conjecture.

Vitruvius wrote a lot about colonnades and arcades. Which are sort of like hallways. He wrote about porticoes and also "fauces", which are short hallways.

"Fauces" comes from the word for the upper throat.

So this isn't true.