why are you such sure? even there will be better digital currency than bitcoin, but people still stay on bitcoin, so what? bitcoin will not die.
so don't judge too fast
The people who is spreading the news that bitcoin is dead may have lost a big amount of bitcoin or just really hates bitcoin that much that he/she is calling it dead while there are a lot of other crypto that is in much worse situation than bitcoin.
One thing is sure, and that's the fact that groups of shills try to make Bitcoin look bad with their lies and fud spreading.
Some get paid to do it, and some didn't manage to buy at the lower levels, or bought high and sold low in panic. There are plenty of reasons why they do this.