Meaning may have a larger existence as a direct product of its have no existence beyond individual mental associations. Symbols may exist as fuzzy isomorphisms across minds, transferred to verbal, textual or other forms then reconstituted. Below a given threshold of accuracy, many minds will identifiably share a concept. Above a given level of accuracy, none will. Miscommunication, ambiguity and other edge-cases don’t falsify the existence of meaning: the fact that they are identifiable strengthens the case for meaning.
This does not give us timeless or metaphysical meaning, but it does give meaning that will last as long as humanity and its media do, and beyond the arrogance of any given individual or group. Which is as much as is possible given a non-deistic worldview.
Semiotics must quantise this mental fuzziness to grep symbols, otherwise it has nothing to work with. Once we have a system of quantised symbols, these can be mapped into another system, assuming that that system is sufficiently powerful (pace Godel or Turing). Communication is therefore possible, unless this won’t work, in which case semiotics is impossible anyway.
Quantising an already quantised system can result in loss of information, so this makes communication problematic. However it also introduces the possibility of generating meaning, as the system being mapped into must extend or create new structures to allow isomorphism. Blah blah blah metaphor blah blah blah.
Any reduction of art, or indeed language, to an unambiguous, discrete system will make it tractable to theory but have none of the expressive power of the system supposedly being studied. I would further state that any attempt to do so is unlikely to ethically survive historical or psychological deconstruction.
What does this have to do with aesthetics? Aesthetics is concerned with the surplus value of symbol systems, with the interrelation of the structure rather than the arcs of the structure. Semiotics is concerned with the structure (allegedly). Semiotics is an aesthetic, a way of seeing the world. It produces symbols from symbols, it has a stopping problem like deconstruction. Its structures need analysis in terms of their interrelations. Semiotics needs aesthetics.
Forget semiotic aesthetics. What’s needed is aesthetic semiotics.