I encountered this issue recently. I wanted to read an old paper of pretty narrow interest, published in a long-defunct journal. In its day, within the relevant

I encountered this issue recently. I wanted to read an old paper of pretty narrow interest, published in a long-defunct journal. In its day, within the relevant small community, it was considered a quality paper by a respected author; it was not some obscure paper that no one ever read. It isn't officially available anywhere today. There's no invisible hand to save those old publications from being lost to time. Happily, with the help of strangers online, I was eventually (after many months) able to get my hands on an electronic copy. The formal system of publishers was of absolutely no use, and the fear of copyright trouble is likely the reason the paper isn't easily available from some online archive. Doubtless there's no profit in preserving such papers formally.