The olfactory sense is just not the same in all people. Some are far more capable of identifying things others just never notice.
There are people, some here at SMF, myself included, who can smell lard in soap. Even as it gets older, it has a distinct odor that can be identified by some folks. I also recall reading here about a woman who could always identify a soap that had Olive Oil in it simply by the smell.
Some examples: Many medical professionals are able to identify infection by smell, but some more acutely than others. At least 2 of the nurses here at SMF have posted about our experiences with that particular oddity.
During pregnancy, some women develop hyperosmia, but this normally goes away eventually (sometimes after giving birth; sometimes before). Others may have hyperosmia for a variety of reasons that can be short term or long lasting, and even life-long) . Sometimes certain olfactory senses can be developed and trained (such as for perfumers.)
Describing the smell of lard as 'weird' would be a misnomer, I think. It's just a smell. To me smells are distinct, not weird. Once a smell that I cannot identify is identified (I search until I locate where it originates), I do not think it is a weird smell. It just is. So if I walk into my house after being gone for a month and notice something smells 'off' or not what I expect, I search until I can identify what it is. Then of course, I deal with it as needed (example: I may come home to rotten potatoes or moldy oranges or some other produce that has lost its freshness.)
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Back to topic: @michael732, I did not start out using animal fats in soap, and do not use soap with animal fats for soaps I use myself. I did eventually decide to make soap with animal fats for some of my family (who don't share my bathroom) because they have no personal dislike for animal fats, so I figured, why not. Just because I am a vegetarian doesn't mean my husband has to be one, so I do occasionally cook meals for him that includes meat, and since I do that, I decided I could also make soap with animal fats now and again for my brothers. So I do that.
Anyway, since I have little to no recent experience using soaps with animal fats myself, I may not be a good judge of what is a good substitute for lard if you want a straight-off 1 to 1 substitute; I can't say I would know the difference or even recognize if there is one (a difference in feel, etc.)
But I can tell you that for the dedicated vegetarian or vegan, especially if they have been one for as long as I have been (about 22 years), a straight-up 1:1 substitute for lard is not at all necessary. Maybe a newly dedicated anti-animal-fat-in-my-soap person, it may matter to them, but for the person who has never used or hasn't used for many years, a soap with animal fat, the need to find a 'perfect' substitute is really not necessary.
As a user of soap without animal fats, I can say there are plenty of soaps you can make without using lard, tallow or other fats derived from animals that are plenty satisfying to many folks who don't want animal fats in their soaps.
I just started making recipes in whatever
soap calculator I was using at the time and was happy with most of my results. I attempted to follow the guidelines for 'acceptable' numbers in the calculators to get a 'balanced' bar and via trial & error, found many recipes that work just fine for me and my family, and some that I absolutely love. In the beginning all I gave my family were non-animal fat soaps, so when I started giving some of them soap with lard, many were quite surprised that I even made it; some didn't like the change, and then some have an 'ick' factor with lard so didn't even want the lard-containing soap anyway.
Other oils to use for making a bar harder and/or longer lasting include:
Cocoa Butter (and the other butters - many recipes use a combination of Cocoa Butter & Shea Butter)
Soy Wax (I use GW415 or equivalent) But some folks don't want any soy in their products, either, sooooo....
Palm (although I never planned to use palm oil in my soaps, I did eventually try it & still use it sometimes)
Olive Oil (Castile soap made with only olive oil is a very hard soap, not so long lasting, though)
High Oleic versions of soft oils instead of the lower oleic versions (Sunflower, Safflower...)
Isolated Stearic Acid can be added to harden & prolong the life of soap but has its own quirks (higher necessary heat, faster trace).
Salt can be used as an additive to make soap harden sooner (doesn't really prolong the life of the bar, IME.)
Beeswax is okay in the eyes of some anti-animal fat folk, but not all, so it's a bit on the iffy side, depending on your audience. Same for palm oil, in case you haven't noticed.
In any case, you can't please all the people all of the time. One won't want animal fat. One won't want palm. One won't want soy. One won't want Beeswax. One won't want lye soap. The list goes on and on.
Incidentally, Avocado Oil seems to give a very nice feel to soap, and one recipe that surprised me with how luxurious it feels to my skin is Avocado (40%), HO Safflower (45%) & Coconut oil (15%) with cornsilk as an additive to the lye water. I originally made this while traveling in 2018, and made soap with what I could find in a grocery store that day. I had read many positive reviews of using high amounts of avocado and of course, the high oleic version of safflower oil is often preferred over regular Safflower oil to make a harder soap and to ward off rancidity. I usually use silk in my lye solution, but that day used corn silk I had 'harvested' from cob corn when preparing the cobs for consumption. So I can't say which specific ingredient gave this soap that fabulous feel, but I suspect the combination is what did it, although one ingredient may have contributed more than another. Although I have used corn silk before, I have not felt that alone it makes that much of a difference to the feel of the soap when it is the only change to the formula.