According to the coolingPerTick function, the temperature gets added to how much a fission reactor cools per tick, which means the hotter the biome is, the faster it cools down. Is this intentional?

Since Minecraft biome temperatures range from -0.7 - 2.0, the current implementation breaks reactors in a biome with a temperature of 0 (Frozen River, Frozen Ocean, Snowy Plains, Ice Spikes), and reactors cool less for biomes with a temperature less than 0 (Frozen Peaks, Jagged Peaks, Snowy Taiga, Snowy Slopes, Grove). Source: https://minecraft.wiki/w/Biome#List_of_biome_climates