It's not just about a currency usage network effect but also about speculative investments and alternative ways to "store" money. Depending on this you can compare it more with stocks without a company behind the stock or gold which for arbitrary reasons can't be used in manufacturing.
Without this and usage for criminal purposes bitcoin would be worth a fraction of it's current worth and as such likely not worth mining for.
This also means IMHO that Bitcoin as currency not just already failed, but did so pretty hard.
As a non currency speculative investment/mony parking product it didn't fail. But it wasn't meant to be such a think.
Furthermore the massive environmental problems it introduce by having a high such a absurd high need of energy and other economical problems (drain of currently limited chips without producing "general" economic benefits, usage for criminal activities if combined with mixers etc.) makes it a highly flawed product.
It should be noted that this is Bitcoin specific. Other cryptocurrencies have this problem much less by neither having absurd high energy costs, nor having absurd high purely speculation/money parking based prices.
Sure there will always be some drain of energy and some drain of chips and some usage for criminal activity. It's just that for Bitcoin thinks have gotten out of balance and besides availability through the network effect there is no reason to use Bitcoins for normal (legal) payments. It's just too costly, slow and price unstable (due to speculative investments always forming a bubble) to be used for normal payments IMHO.
Exceptions can be countries with a "broken" economy, but even then other crypto currencies would be normally preferable as far as I know.