Vanguard has sector funds which divide the market by category.
You might be surprised to only find a couple stocks in the "Information Technology" sector of the market, represented by Vanguard Information Technology ETF (which tracks an MSCI index).
It's top 5 holdings are : Microsoft, Apple, Visa, Intel, Mastercard.
To find Amazon, you need to look in Consumer Discretionary.
It's top 5 holdings are : Amazon, Home Depot, McDonalds, NIKE, Starbucks.
And finally there's Vanguard Communication Services ETF (VOX) where you'll find Google and Facebook:
Top 5 holdings : Alphabet (Google), Facebook, AT&T, Verizon, Comcast.
When tech companies were new, that was a category. Now everyone owns a smart phone running Apple or Google's software. People visit Facebook and shop with Amazon. They're a part of daily life, and they have settled into different sections of the stock market. That's the view Vanguard and MSCI reflect in their categories.
If their categories are incorrect, there should be some event/situation that impacts only "tech" companies but leaves "non-tech" companies unscathed. There should be a reason the distinction between "tech" and "non-tech" companies is meaningful.