Oh, I read that post several times because it kept coming back as results in my searches. It is exactly the problem I have, and the OP solution is exactly what I implemented.
It’s a philosophical debate as to what it should be and can’t be determined at compile time – meaning by the ZWave (or other) database maintainer. I never used OH1, but apparently OH1 allowed one to remap one type of Item to another type of Item.
So, as far as I know, the workarounds require virtual items and rules as proxies to the proper types, or working in the sitemap and parsing values as strings, or remapping there.
There is probably a developer discussion somewhere that discusses this issue. It used to be in OH1, and it’s not in OH2, so someone must have discussed it, or maybe it’s on the OH2 roadmap. I haven’t discovered this discussion yet.