I haven't read that they maintain their youthful appearance indefinitely. There is also a great deal of conflict in the lore on life span of mer. I have read more than a hundred years, I have read as many as a thousand years. The more recent literature in the franchise points to the former.
This mod has a mirage of options. While for Core the recommended "All NPCs" version is okay, as long as the STEP patch is used it should remain okay for Extended as well. If the STEP patch is not used, the All NPCs BOYD Compatible Loose Assets optional version should be used.
I would like to challenge this by changing the recommendation to the All NPCs Loose Assets optional to keep in line with STEP's recommendation of using loose files whenever possible. I would also like to recommend adding the No Elves optional file to the recommendation to keep the mod lore friendly.
They are among the longest living and intelligent races of Tamriel' date=' and they often become powerful magic users due to both their magical affinity and the many centuries they may devote to their studies. Source: https://www.uesp.net/wiki/Lore:Altmer[/quote']
It is common knowledge that elves, in any lore, have outstanding longevity and live to be very old while keeping their fare, young complexions. For this reason I recommend we include the No Elves optional.
I think it is best in this case to look at the historical precedence for how age is portrayed in the ES games. In the ES games, there are elderly mer. In Skyrim, the voice for the older mer is different from that of regular mer, and their appearance differs too. It seems to follow that the consistent older people mod could extend to both human and mer races.
Also, I think you have to consider the intent of the mod. The intent of the mod is to resolve conflicts between appearance and description of characters. A great example, the high elf that gives you the quest to retrieve the white phial in windhelm. He is described as near death, his history suggests he has lived a long time, and the voice actor used is the one used for other older characters. It makes sense that appearance should reflect that (provided that mer can age at all).