Idiomatic phrases usually (but not always) retain a stress pattern that corresponds to the prosody of their original syntax even after they lexicalize. See: “the CAT’s out of the BAG” vs. “the CLAM’S out of the POND” and “kick the BUCKet” vs. “beat the MONkey”.
So, while I agree with you that “time being” (and probably all of “for the time being”, for that matter) is idiomatic, its prosody has fossilized from its original syntax in which “being” modified “time”.
“LET’S put it aSIDE for the time BEing”
“LET’S put it aSIDE for the man EATing”
Also, even if the stress has neutralized from “time BEing” to just “time being” over time for some speakers (which is certainly possible), it would still contrast with “TIME being”.
This is a good point worth commenting further on.
Idiomatic phrases usually (but not always) retain a stress pattern that corresponds to the prosody of their original syntax even after they lexicalize. See: “the CAT’s out of the BAG” vs. “the CLAM’S out of the POND” and “kick the BUCKet” vs. “beat the MONkey”.
So, while I agree with you that “time being” (and probably all of “for the time being”, for that matter) is idiomatic, its prosody has fossilized from its original syntax in which “being” modified “time”.
“LET’S put it aSIDE for the time BEing”
“LET’S put it aSIDE for the man EATing”
Also, even if the stress has neutralized from “time BEing” to just “time being” over time for some speakers (which is certainly possible), it would still contrast with “TIME being”.