KDE System Setting Font hinting sample looks the same

KDE System Settings font hinting sample looks the same. I want my font to look sharp and crisp. What seems to be wrong and how can I fix this? I have attached the screenshot below.

Settings details:

Operating System: Kubuntu 25.10
KDE Plasma Version: 6.4.5
KDE Frameworks Version: 6.17.0
Qt Version: 6.9.2
Kernel Version: 6.17.0-19-generic (64-bit)
Graphics Platform: Wayland
Processors: 16 × AMD Ryzen 7 PRO 4750U with Radeon Graphics
Memory: 32 GiB of RAM (30.1 GiB usable)
Graphics Processor: AMD Radeon Graphics