How thin can we make pilot suits?

[False Prophet]

I'm not very well acquainted with the anatomy of pilot suits, but wouldn't there be a lot of things that go into them if we want someone to pilot a machine that work in very high attitude or even space? Like, insulation, fire-retardant, protection against radiation, something to counter the blood loss caused by G-force, etc. There is no way a latex suit is going to be able to pack all of these, right?

Maybe that is another brilliance of LCL from Evangelion. That fluid can do a lot of these things so that the pilot suits be designed to be tight-fitting like they are.

[Kuruni]

Very thin. Try look up Sayaka Yumi's Artemis A's pilot suit in Shin Mazinger Zero, or the Mazinsaga version.

As for what's required for a pilot suit, it's depend on the story. For examples, VangRay from SRW V boast the cockpit with highest safety that it dpesn't require pilot suit at all. While Series 77 (Astelion and its successors) require full astronaut suit.

[MythSearcher]

I'm not very well acquainted with the anatomy of pilot suits, but wouldn't there be a lot of things that go into them if we want someone to pilot a machine that work in very high attitude or even space? Like, insulation, fire-retardant, protection against radiation, something to counter the blood loss caused by G-force, etc. There is no way a latex suit is going to be able to pack all of these, right?

Maybe that is another brilliance of LCL from Evangelion. That fluid can do a lot of these things so that the pilot suits be designed to be tight-fitting like they are.

At least something like this.
https://news.mit.edu/2014/second-skin-spacesuits-0918

You can keep pressure and counter G-force by pretty much the same mechanics, and the Biosuit do it by pulling on strings. If you use tubes with fluids moving in it for heat exchange, that can also reduce the required structures.(we just need to have strong enough tubes)

Latex is a bit hard, but if you look at those dry type divers suits: https://en.wikipedia.org/wiki/Dry_suit
Insulation isn't really that hard to do.(but you will need to design for radiation heat transfer as well.)

[Mafty]

Sunrise Mech shows seem to have a pretty good middle ground on this, particularly during the Real Robot boom of the 1980s. The clothing often seem like a cross between a flight suit and space suit, and look like a motorcycle suit. Furthermore people can often wear their clothing underneath these suits(something seen in various Gundam shows in the 80's as well as Layzner).

As for the Eva Plug Suits, often the Eva's don't go into space, so that probably helps somewhat.