If we didn’t have a bazillion TLDs these days we’d be ok and everyone can carry on using .local or .lan and be happy that they’re not real TLDs. Now when anything could be a TLD because every word you’ve ever heard is a TLD, you don’t know if its real or not.
Reserved TLDs are documented. The issue is they prioritized all the crazy ones before they added what people at home and businesses were actually using. ICANN won’t sell .lan because it is used too much. They haven’t tried so there is no official decision, but they won’t - they did try .corp and .home and abandoned it.
.local is reserved in RFC 6762, but for multicast DNS.
People have been told for a very long time not to use fake TLDs. I don’t think it’s reasonable to accommodate people who can’t follow instructions.