To be fair, the ambient temperature being 37°C versus 0°C already makes a significant difference in terms of e.g. the air density and the amount of lift the wings get, how easy or hard it is to start up the engines, whether ice is a problem, etc.
If the 15% difference in delta also translates to a 15% cost/efficiency difference, then that can absolutely make the difference in whether the technology is economically viable to apply at scale compared to its alternatives.