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Resize image too blurry (down scale)
#1
Photo 
Is there any way to deal with this?

Here's an example, resize to 25%.
Gimp - blurry. (if choose None, will get terrible aliasing)
Windows Paint - not blurry (but not support alpha).

Original image (cannot attach, said too large): https://1drv.ms/i/c/cfd39d12afb55641/IQB...Jss9bfcMkA
Result-Gimp: https://1drv.ms/i/c/cfd39d12afb55641/IQC...ceDmBBTfrU
   
Result-Windows Paint: https://1drv.ms/i/c/cfd39d12afb55641/IQA...EO4nLDEi9Y
   

Look at the face and hair.

edit:attachment seems didn't display.
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#2
The scaling algorithm to use is LoHalo.
quote: LoHalo method: when you downscale an image thats less than a half of the original size

It looks to me that the MSPaint scale also incorporates an automatic degree of sharpen. As a comparison.
(1) Scaled with Gimp 3.0.8 LoHalo
(2) Your MSPaint example. I can see a small amount of "fringing" that forehead detail for example.
(3) A default value unsharp mask applied to (1).  There are other (possibly better) sharpening tools, I often use one of the gimp_gmic_qt filters.

   
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#3
There is a new filter in version 3 of gimp under enhance, to sharpen which doesn't do a bad job called sharpen deluxe.
I downloaded your file, sharpened but it wont save/export. My antivirus doesn't like it.
(Weird that it let it download but wont save from gimp)

Smile
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