I understand that within limits. Planning one's retirement shouldn't be an adventure in uncertainty like that in my mind. I think those of us who began doing this 50 years back just loved the comics for the most part. I mean Howard Rogofsky was just about the only one selling comics. If you bought it then, it could be a major score both as a curious piece of ephemera and amazingly developing value. I don't see it quite that way these days. Between cap gains, commissions, shipping, slabbing, unsure auction results, it takes a book, or a bunch of books worth $100 or more to make it viable. I doubt they were bought in the last five years.
The point being that if you got in early, it's fine. If you want to inquire about buying comics as an investment now, that ship has sailed at least as a retirement income from the dollar box. They are still a lot of fun.