The question is not which regime is better
It is which regime is better for you, and that turns on one number: how much you genuinely claim in deductions and exemptions. The new regime offers wider slabs and a lower headline rate but strips out almost everything you can subtract. The old regime keeps HRA, 80C, 80D, home-loan interest and the rest, but taxes what remains at higher rates.
So there is a break-even: a total deduction figure below which the new regime wins and above which the old one does. This tool computes that crossover for your salary rather than leaving you to guess, which is the part most comparisons skip.