I don't think anyone thinks 1.5 degrees is feasible (we've probably already gone past it), but the options should be around changing that measure (to 1.7 or 2.0 or whatever), not gutting large parts of our legislation.
A steady (and fast) reduction in emissions is required to be consistent with 1.5 degrees. That's what the emission budgets do. The 2050 target is insufficient by itself
The changes are setting us up to miss our current international commitments and to slow emissions reductions after that