The term bubble is being used when there is need to discredit something. Before the 2008 stock market crash when the price was just going all the way up it was being interpreted as increase in activities, confidence boosting in the market, awareness is getting to a high level and all of the technical jargon that is being used to justify the financial charade that happened until everything came crashing.
On the tech stock, despite the increase, it still would not be categorised as bubble because they don't want to discredit the new funnel that people is interested in and just like you said, it wont last forever as every model has its own expiry date I only pity those who believe they can invest in this for a long term purpose. On crypto currency that cannot be controlled, that's where phrases such as ponzi, bubble, scam, multi percentage growth is paramount in other to kill it.