Who are they who still consider btc as a failed project? BTC will certainly double in value from its current value when the market booms. Those who think BTC is a failed project will surely regret it. There are many investors who don't care about BTC price but they care about saving BTC. And they invest in Bitcoin for long term. Although the market is always unpredictable, there is no reason for anyone to despair of investing in Bitcoin. Of course Bitcoin will do well in the future.
Maybe only people who don't like Bitcoin completely say that Bitcoin is a failed project because apart from not understanding how a project is successful, they also may not understand what technology is contained in Bitcoin itself so it is easy to say that Bitcoin is a failed project so people like They don't want to own it because basically people like that don't like Bitcoin either. So it's actually quite simple to know this because investors who have made several profits through Bitcoin will still remember Bitcoin and will not easily forget about it.