Why was 滾 (gǔn) simplified to 滚?
"Simplified Chinese" is not the clearest name, because it refers to the entire standard character set of the PRC. Although the majority of characters different in the PRC compared with other regions are indeed "Simpler" (by measure of stroke counts), this is not true of all characters. Some examples where the PRC standard have more strokes, whilst still being called "Simplified Chinese", are「强」and「榨」(other regions tend to use「強」and「搾」, which both have one less stroke).

Formally, a "Simplification" process is an active attempt to cut strokes off characters, by removal, abbreviation, or replacement of components. This is not the only way that characters change, and in fact the vast majority of characters did not change in the direction of "Simplification"; many did not change at all, and among those that did change, the majority became more diversified over the years, with components added to create new characters to express new words or extended meanings.

Choosing variants which just happen to have less strokes, as is done in「滾」vs「滚」, is not "Simplification" -「滚」was merely a variant chosen as part of a standardisation process.



The component「袞/衮」(Emperor's ceremonial robes) is comprised of semantic「衣」and phonetic「公」. However, this does not mean that in「袞」,「厶」was changed to「口」. On the contrary,「公」originally looked like「㕣」.

「公」originally depicted a pottery jar, and this word is now written with variants「瓮」and「甕」.「八」depicted the handles of the jar, and「口」depicted the jar's opening.

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Squares and circles were not the only representation of this opening, and later on,「口」was subject to shape variations, with some becoming triangles or stylised into「厶」.

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