Why Were Old Thai Fonts So Small

The Facebook page Cadson Demak has provided an excellent explanation for why old Thai fonts were so small. You can read their explanation here.

Summary:

In the past, diacritics (วรรณยุกต์) that extended beyond the bounding box of the base character would not be displayed correctly. To address this issue, font designers would reduce the size of the entire character set to ensure that all components, including diacritics, remained within the visible area.

However, modern display systems and font rendering engines can accurately render diacritics regardless of their position within the bounding box. Therefore, there is no longer a need to reduce the size of Thai fonts to accommodate diacritics. Current Thai font designs should adhere to standard font sizes to ensure consistent and optimal readability.