[roland35]

For your retirement, yes diversify. Knowing and understanding technologies isn't the same thing as knowing and understanding tech stock. Just look at Peloton as an example - they did great during the pandemic, but just had a child die because of their treadmill and now lost 15% in a day. The US Government could break up Facebook tomorrow. Who knows? If you want to try and gamble do so with a little bit and see if you can beat the SP500 over a few years :)

If you invest in broad index funds in the long run (10, 20, 30 years) you are guaranteed to beat almost all actively managed funds. Fees are going to eat away at your gains and again most active investors can't beat the market in the long term. I use FSKAX with Fidelity but VTI is a similar ETF.