I believe the transition most likely occurred in a similar manner to the phrase “she has a great personality” when responding to the question, “is she attractive”. It’s not that anyone dislikes a great personality it’s that an honest answer to the question of her physical attractiveness is being avoided. When it had been used enough it becomes cliché and the word or phrase takes on a new meaning. Like wise homely used to be a compliment, but it may have been used so often the way “she has a great personality” has been that the meaning became a negative.
I'm only 67, but to call a woman homely has been a cut my entire life, and that predates feminism gaining a foothold, so this has nothing to do with negative views of the home -- and if that were the history of the etymology 'homely' most certainly would have become a pejorative in the British Isles by now as well. I still think it reflects a bias that you came up with that. It would be just as accurate to posit that it's a compliment in the former British Empire because Brits like their women to be ugly.
Here from etymonline.com, and note toward the end that there are associations with looking like a corpse:
homely (adj.)
late 14c., "of or belonging to home or household, domestic," from Middle English hom "home" (see
home (n.)) +
-ly (1). Sense of "plain, unadorned, simple" (as domestic scenes often were) is late 14c., and extension to "having a plain appearance, without particular beauty of features, crude" took place c. 1400, but survived chiefly in U.S., especially in New England, where it was the usual term for "physically unattractive;" ugly meaning typically "ill-tempered." In the old sense of "domestic, of or pertaining to domestic life," homish (1560s) and homelike (1789) have been used.
Entries linking to homely
home (n.)
Old English ham "dwelling place, house, abode, fixed residence; estate; village; region, country," from Proto-Germanic *haimaz "home" (source also of Old Frisian hem "home, village," Old Norse heimr "residence, world," heima "home," Danish hjem, Middle Dutch heem, German heim "home," Gothic haims "village"), from PIE *(t)koimo-, suffixed form of root
*tkei- "to settle, dwell, be home." As an adjective from 1550s. The old Germanic sense of "village" is preserved in place names and in hamlet.
'Home' in the full range and feeling of [Modern English] home is a conception that belongs distinctively to the word home and some of its Gmc. cognates and is not covered by any single word in most of the IE languages. [Buck]
Slang phrase make (oneself) at home "become comfortable in a place one does not live" dates from 1892 (at home "at one's ease" is from 1510s). To keep the home fires burning is a song title from 1914. To be nothing to write home about "unremarkable" is from 1907. Home movie is from 1919; home computer is from 1967. Home stretch (1841) is from horse racing (see
stretch (n.)). Home economics as a school course first attested 1899; the phrase itself by 1879 (as "household management" is the original literal sense of economy, the phrase is etymologically redundant).
Home as the goal in a sport or game is from 1778. Home base in baseball attested by 1856; home plate by 1867. Home team in sports is from 1869; home field "grounds belonging to the local team" is from 1802 (the 1800 citation in OED 2nd ed. print is a date typo, as it refers to baseball in Spokane Falls). Home-field advantage attested from 1955.
-ly (1)
suffix forming adjectives from nouns and meaning "having qualities of, of the form or nature of" (manly, lordly), "appropriate to, fitting, suited to" (bodily, earthly, daily); irregularly descended from Old English -lic, from Proto-Germanic *-liko- (Old Frisian -lik, Dutch -lijk, Old High German -lih, German -lich, Old Norse -ligr), related to *likom- "appearance, form" (Old English lich "corpse, body;" see
lich, which is a cognate; see also
like (adj.), with which it is identical).