I don't have reasoning for you, since I didn't write it ... but I can share the general view of LFE development which could very well have informed the reasoning behind the current system.
LFE is definitely a Lisp, but it also definitely rests on the Erlang VM. Since the whole point of LFE was to make a Lisp that was 100% compatible with Core Erlang, many of Robert's design decisions have ensured that those coming from Erlang would have everything they had in the original dialect. I'm guessing this might explain the situation with these functions/macros in LFE.
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