The article linked below discusses current valuations compared to the Dot.com era. From the article

"Only the dotcom implosion was an equity bubble," says Barry Ritholtz, CIO of Ritholtz Wealth Management, noting that a bubble is typically an asset class that becomes un-moored from intrinsic value, that leads to excessive speculation, that leads to a giant market crash.
He echoes the broad consensus that while the 'Magnificent 7' clutch of mega tech stocks powering the market higher are expensive, they are not in that space yet. Expectations of $2 trillion in revenue and $300 billion profits this year see to that.
"Are they above fair value? Probably, but all great stocks are. Fair value is not a magnet that automatically draws markets there. In fact, stocks rarely find themselves at fair value," he says.

There is also a graph that shows PE values for the tech sector. Usually, graphs only show the SP500 PE values which currently appear quite high, but the current tech values do not.

reuters.com - Stock market crashes are rare equity bubbles even rarer mcgeever

For those with momentum screens, no need to panic yet????

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