for 形聲字, the simplification made severe, unrepairable damages to the chinese culture.
for example, the character 難(u+96e3); it's composed by the 172th radical 隹(u+96b9); and the component (u+26c29), that's a phonetic component, which was shared by numerous characters.
the 說文解字 stated: 難 鳥也﹒從鳥﹒堇聲
while 堇(u+5807) is a character since oracle script,
; later, it's derived to 堇(u+5807)
& (u+26c29)
back to the phonetic component 堇. in cantonese, 堇 is pronounced as gan2 sound file, which has the 韻母 (final) "an".
so, characters share this phonetic component 堇, guess how they pronounce?
難(u+96e3) naan4 sound file
嘆(u+5606) taan3 sound file
艱(u+8271) gaan1 sound file
after thousands of years, the 韻母 (final) of these characters are changed slightly from "an" to "aan", isn't marvellous?
therefore, the simplified script of 难, 叹 & 艰 lose the phonetic component 堇; that no-one in modern time, or generations in the future would associate the correct pronunciation from the component of the simplified character.
c'est patrimoine culturel perdu ☠
lastly, i think that this question is excellent; i worried about the temporary "hold on" status of it. may i ask the rationale of this decision?