If it costs more to precisely meter than the savings for 99% of individuals, it was a bad (forced) program to upgrade to smart meter infra - it's not free. Could have invested the money into demand reduction (free LED bulbs, insulation loans etc.) or supply improvements.

Don't overspend on getting to 100% fairness.

Same reason why if you ask for a meter audit, they'll do nothing if it's +/- 2%, even though anything other than 0.000000000000000000000000% error is unfair.