Default 4.x editor theme is way too zoomed in (32-inch 4k at 100% system scale)

[lyuma]

Godot version:
4.0.dev d1dc28e

OS/device including version:
Windows 10.0.19041.928

Issue description:
I lost my editor theme and now my editor is so zoomed in it's almost unusable.

It shows here that the setting is Auto (150%) but it feels to me more like 200% or more compared to other apps. If I can read my browser text at this size, there is no reason for Godot to be making the default text size larger.

Here is a screenshot showing the settings screen. The browser screenshot is for reference as to my desired default font size:

Somewhere between 50% and 75% ought to be the default on my system.

Steps to reproduce:

1. Use a 32-inch 4k display set at 100% scale.
2. Navigate to C:\Users\USERNAME\AppData\Roaming\Godot
3. Delete editor_settings-4.tres
4. Open the project selector window.
5. Everything is huge and hardly anything fits on the window.

Minimal reproduction project:
N/A

[Calinou]

This is done by design in Godot 3.3 and later as 4K displays will use 150% scaling by default, regardless of the reported DPI. We don't have a method to read Windows' scaling factor yet, so we have to do guesswork based on resolution and reported DPI instead. However, some display EDIDs are really bad at reporting DPI accurately, so we sometimes just use the resolution to automatically determine a sensible scaling factor.

Most 4K monitors will be used with some kind of scaling, so we chose to use 150% scaling for 4K monitors in 3.3 with #45910. (For instance, if you wish to have the same physical scale and screen real estate on a 32" 1440p monitor and a 32" 4K monitor, you need to use 150% scaling on the 4K monitor.)

You can fix this for your particular use case by setting the Editor Scale to 100% in the Editor Settings.

It shows here that the setting is Auto (150%) but it feels to me more like 200% or more compared to other apps. If I can read my browser text at this size, there is no reason for Godot to be making the default text size larger.

Godot's executable is DPI-aware, so that definitely isn't happening – it's an optical illusion due to the system text being so small in comparison. 75% scaling will definitely look too small to be usable on a 4K 32" monitor, unless you get very close to your screen.