Our level 4 lockdown didn't last very long.

The strictness index (which is what I'm assuming you're referring to) varied over time as the response changed.

The claim I was initially responding to was, "New Zealand locked down less than a lot of countries". Not specifically length. NZ lockdown was especially strict in some regards (level 4, border lockdown) and especially prolonged in others (Auckland lockdown, border and MIQ).