Blurry QQuick rendering of textures on Wayland with fractional scaling

On the screenshot you can see several render cases under Wayland with fractional scale 1.5:

1. Controls.Button with icon.source as SVG – rendered OK
2. Same but bigger – OK
3. Image with the same SVG with a smooth=true – It is blurry, but I assume it is OK
4. Same, but smooth=false – artifacts
5. QQuickItem + QSGTexture + QPainter::drawText – texture rendered with artifacts
6. Same but with Linear filtering – blurry
7. Just for comparison simple Text – OK, but hinting is different from the QPainter(I assume it is OK)

On X11 with the same scale factor:

1. OK
2. OK
3. Same blurry, assume it is OK
4. Crystal clear, without artifacts
5. Crystal clear, without artifacts
6. Almost same result as in 5. Without hard smoothing
7. Same as under Wayland, OK

It is better not to have KDE installed because it interferes with styles and its own Quick implementations. I had to delete the kirigami and qqc2-breeze-style packages while testing this.

Please find attached the test project and screenshots (actually window grabs taken by the grabWindow function because KDE's screenshot tool still produces blurry screenshots )