I'm sure my mother's house was much cooler - what with it pointing North East, being built from double course bricks, wooden suspended flooring over foundations, no insulation, purpose built cold larder and a coal store, chimney and the necessary fireplaces in every room and single glazing with windows on all 3 sides creating air movement, garden and therefore air space and shade going around three sides, designed for air circulation to avoid smoke particles and mould collecting in the house, all the gardens around us full of plants and trees rather than driveways, extensions and blocks of flats in the larger ones, hedges rather than fencing, wide road with large grass verges and pavement planted trees every 6 houses and suchlike.
Swap that for newbuilds crammed in together with zero grass, brick paths on sand, facing SE, no gardens, all the mature trees chopped down in order to build them more easily, lots of insulation, concrete slab foundations and floors, narrow roads and driveways, no side windows because they might overlook a random's garden or cost a couple of quid to install and designed to keep as much heat in as possible.