It might be in a bubble. However, the question is if the bubble will burst and if so, why? Let's assume there's a reason for the bubble to burst, some banker saying something in the news or some fake news about many governments trying to ban it. That may trigger a selloff and during a selloff some people will panic sell.

Now luckily there's some self regulated mechanism in place that will prevent the consequences from becoming too bad which is:

• Tax: selling crypto for fiat means you have to pay tax in most countries, are you ready to panic sell knowing that the price might just go up again and when you buy back you'll have less crypto than before you sold?
• Exchange limitations: exchanges doesn't have infinity amount of money or even high server capacity to handle a massive selloff. Just look at Coinbase and how it crashes every time people start to panic sell, if you can't panic sell your coins you are forced to hodl.
• Hodlers: crypto enthusiasts with beliefs and large amount of crypto who refuse to sell at loss, these are the people who brings stability to crypto.
• Correct news: basically, all "manipulation" works in both directions, people will criticize fake news, provide evidence, calm down the newbies etc..

So to summarize, yes it may be in a bubble but there's nothing indicating that the bubble will burst. This year has been full of bad news with some impact on the price but that hasn't stopped the price from going up 1000% over the year.