I've never understood these "it isn't perfect, so why bother doing it
at all" arguments. The goal of more effective communication and thought
is a worthy one. Even the specific idea of improving language has
clear support as an Extropian goal in things like E-prime, which is to
Lojban as fixing a tail light is to rebuilding an engine.
Your misperception that Lojban has any "philosophy" or "claims" to be
anything is so far off that I can only assume you have learned about it
second hand rather than from the source. Lojban was created as a means
of testing the Sapir-Whorf hypothesis, and designed with that goal in
mind. Its grammar and phonology, based on predicate logic, also make
it well suited for computer processing. That's all. It doesn't "claim"
to be "logical" (whatever that claim even means), and it doesn't claim
to be culture-free, it just is what it is--structured on predicate logic,
and not containing many specific cultural artifacts that have been
identified in other human languages. And don't confuse PCR with naive
skepticism--logic exists; how one uses it is another matter.
It is interesting to note that although Lojban does have the identity
relationship, it is almost never used in normal conversation. Not
because it is deprecated or avoided, just because the design of the
language makes it not particularly useful.
This exchange does answer one question though--since yours is the
only response, it is clear that there is little interest here. Pity.