The monetary reason is that the reason those things go down is because of technology advances and not because of changes in the value of the currency. Inflation should be about the currency, and less about what cool advances people are doing to make cheaper TVs and better websites
The practical reason is that if the basics like rent and food go up relative to wages, then a lot of people end up crushed by the basics alone and have no disposable income left for the cool stuff. The baskets are often too biased towards spending patterns of those who live the good life and for whom luxuries actually matter
Aside from technological and scientific progress in the medical field, it's generally been shown that people's lives have gotten worse.
The quality of the house your grandparents (for 1920 probably your grand-gran parents) is vastly different. Those houses cannot be compared at all, when I take my dump in the heated warmth in a nicely smelling place listening to some music over my airpods.
It's a statistical tool concerning populations, not a sampling of what hacker news user cicko in their wisdom thinks increases quality of life.