No the reason your grandad could buy a 3 bed house was because houses were cheaper in relation to wages. It wasn't that wages were higher.
There was also far, far less stuff that one could have and what society said you should have. When my parents (now both retired) bought their house it was £30,000 (which was about 5 times my dad's annual salary), yet they sold it 20 years later for £250,000 (over 10 times what my dad was earning by that time from the same job).
They didn't have a foreign holiday until they mid 90s, the vast majority of their lives was a yearly trip to Bognor and that was it. They had one TV and the rest of their money went on food and clothes. Now they have a TV in every room, a couple of computers, an e-reader, a car each, several pets, various insurance plans, internet bills, online subscriptions to various services etc.
But like you the harp on about the pre-Thaterchite era not even seeing themselves how much simpler and less stuff you were expected to buy/own was back then.
Your parents grew up in post war Britain, of course they had nothing.