Consumerism is good, it makes the economy gears work fine. On the other hand it has some disadvantages: like people who don't know limits borrowing money, creating a rising debt, possible to bankrupt. And there is a bad kind of consumerism too, the low quality one, like when people satisfy themselves with low quality goods and even pay a disproportional amount of money for it. Then it leads to a low quality industry producing garbage.

About Bitcoin, consumerism doesn't need to change because of it. Bitcoin would just replace fiat. You could borrow BTCs, you could buy anything you want and a lot, if you have enough Bitcoins...

Decreasing consumerism would lead to decreasing the demand, weaking the economies and Bitcoin. Goods' prices wouldn't decrease, only Bitcoin price would. So you would need more BTCs to buy stuff for you.