Compare NPS against an equivalent pure equity mutual fund SIP, at the same contribution and assumed return.
Both sides: Same SIP future-value formula; NPS applies a 40% mandatory annuity split at the end
Does NPS offer any advantage over a mutual fund SIP then?
Yes — NPS contributions get an additional tax deduction under Section 80CCD(1B), separate from and on top of the regular 80C limit, which a mutual fund SIP does not offer. That tax benefit is a real advantage even though the growth math itself is identical.