A/C for everyone is not a need. I live in a considerably warmer place than England, never had an A/C and never desired one. I live just fine and don't feel the need for an extra appliance cluttering my home. Most people around here do just fine without A/C.

Houses are built according to the needs of the place where they are built.

This is indeed a problem happening right now, this is a good temporary solution. I do believe a better structural solution to this problem may be required, but I don't think that would be to add A/C to all houses.