The UA's filtering on LH/SQ/TQ award seats has been discussed ad nauseam here on FT.
Personally I don't believe that there are any "quotas" assessed by other *A carriers to UA. UA simply doesn't want MP members to redeem on other *A carriers that would result UA actually paying them.
OP's rant has nothing to do with NH that provides excellent tool for *A redemption seat availability. I just hope that these "rants" don't make the tool to disappear.