People have been saying this ever since Bitcoin came into existence. The moment it crossed 500$, people start speculating that the bubble would burst and it wasn't until it reached 20k$ that the bubble actually bursted. The price will stay in this range for a couple of years now and we might see it cross 10000 dollars by the year end. Apart from that there is NO BUBBLE and it WON'T BURST! So relax.
I know many people said bubble for bitcoin when it was $300 and those people never accep that they were completey wrong about crypto. This is very sad for them because they totally missed the party!