If the font is too reductionist or ornamental in its visual representation, then it absolutely will be harder to parse, and that's where the designer's skill comes in -- through little strokes/serifs/curves/movements/etc. -- to remove ambiguity and evoke familiarity.
As with any writing system for any language, human eyes quickly scan the general outline of a letter to recognize it, so if the "soul" of a letter is still there in the new font, then our minds won't have too much trouble re-mapping it to the "default/classical" form.
For an example of this minimal "soul" of a letter, sometimes all I need to know is that one side is fatter than the other... or that a serif slants to the left or to the right... to be able to distinguish between two possible options.
I imagine those curvy, cursive fonts of Chinese characters in Chinese or Japanese calligraphy are probably recognizable to their readers in the same way.
So, yes, they are, rather largely, readable to me.