The lack of a proposed solution does not make the identification of a problem worthless. Writing code is as much part of the process of solving problems with software as identifying those problems is. When a problem is largely a social one, rather than a technical one, identifying the problem and making people aware of its existence is often the bigger part of the process.

Tor guarantees anonymity. It succeeds at that. There is no technical problem. There is no code to write. This could lead you to think there's a problem with scope, that maybe Tor should guarantee security too. Unfortunately, the design of Tor is not compatible with that goal: if your plain text data goes through an exit node, then by definition, that exit node gets to see what the data is. A bug report titled "Tor does not provide secure communication" would get closed faster than you can say "won't fix". And rightfully so.

There is, however, a social problem, as stated by the OP: many people actually expect security. This is a problem that can only be solved by educating as many people as possible that this is the wrong expectation to have, which is what the OP is contributing to by making this post. This is very much in the spirit of "if you think it should be done, do it".