It's at least plausible that the population did increase. Estimates of births during the war are larger than the casualty count that Hamas claims.
Gaza population September 2023: 2.3 million. Gaza population September 2025: 2.1 million.
Hamas casualties make up only a portion of palestinian casualties; palestinian casualties make up only a portion of excess deaths; excess deaths make up only a portion of total deaths.
Estimates of birth that rely on the mid-2023 figure and deliberately ignore Israel's systematic dismantling of the health and food systems in Gaza and the drop in fertility levels.
>the casualty count that Hamas claims
The Gaza Health Ministry's count is widely regarded as an underestimate, but mostly by people who don't refer to it with a dogwhistling caveat.
It'd be nice if Israel would let UN fact-finding missionaries or other independent research teams into Gaza to find out (in addition to not barring and/or killing humanitarian aid workers)