I agree with your overall statements. I don't mean to nit-pick, but just thought I would clarify some of the phrasing in bold as it relates to a proper understanding of shoe construction. Also, I apologize if you were referring to shoes as a whole rather than shoes that are typically discussed in this thread (bespoke, hand-welted, or quality goodyear welted). Moccosin construction, Blake stitched, and others do pose some different scenarios, and I am not including those. That said, I think that unlined shoes are generally an exception to the rule, and they aren't very common. Generally unlined shoes are suede, or sometimes shell cordovan, and the manufacterer is going after a more flexible supple shoe right off the shelf. Most shoes are fully lined. The sock liner is not synonymous with the shoe liner. The sock liner is simply the piece of leather that is resting under your foot (between your foot and the insole) and often has a cushioned heel pad. Allen Edmonds does not use sock liners in most of their shoes, so your foot is directly resting on the natural leather insole. Alden, and most others uses a 3/4 length sock liner, and some use full length sock liners. Typically, bespoke and hand-welted shoes are likely to have a full length sock liner to cover up the ugly nail holes that result in the leather insole during shoemaking. The insole of quality goodyear welted shoes is leather. Cheaper goodyear welted shoes may use leatherboard or fiberboard insoles. Cork is filling the void created by the gemming rib under the insole, between the insole and the outsole. Allen Edmonds and every company that is "better" than them, uses cork as a void filler underneath a natural leather insole. Obviously if we start talking cheap shoes (cemented, or other) then there are many variations on how shoes are made, but I think it is safe to assume that most in this forum are concerned with one of the types of shoes mentioned above. Again, sorry to nit-pick, but shoe construction is a big interest of mine.
Thank you for the clarification on the sock liner / shoe liner distinction. I found your more detailed explanation of the insole construction helpful as well. My point being that there is a greater moisture barrier between the bottom of your foot and the leather sole, than there is between the top of your foot and the leather upper.
I am here to learn as much as I can, while also sharing my current understanding. I welcome any knowledgeable clarifications or corrections, and it benefits the membership as well.