That is bad advice.
VGT Vanguard Technology ETF has outperformed S&P 500 over the past 20 years.
All the people who say “VTSAX and chill” disappeared in the past 3-4 years because their cherished total passive index fund is no longer the best over long horizons. And no, the markets are not efficient.
Given the techie audience here, I want to caution that investing in the same industry as your job is a kind of anti-diversification.
A really severe example would be all the people who worked at Enron and invested everything in Enron stock.
Even if your employer/investments aren't quite so fraudulent, You don't want to be in a situation where you are long-term unemployed and are forced "sell low" in order to meet immediate needs. If only one or the other is hit, you can ride things out more effectively.