I think VGT is a good QQQ replacement. It is based [1] on the MSCI US Investable Market Information Technology 25/50 Index which is free-float adjusted [2] [3], meaning that SpaceX will have a lower weight due to its lower free float. Also, VGT has a substantially lower expense ratio (9 bps / year [4]) than QQQ (18 bps / year [5]). You can compare VGT and QQQ's holdings on these pages [6] [7].
[1] https://fund-docs.vanguard.com/F0958.pdf
[2] https://www.msci.com/indexes/documents/methodology/2_MSCI_25...
[3] https://www.msci.com/documents/10199/6bafd9e3-0474-f03b-16bd...
[4] https://investor.vanguard.com/investment-products/etfs/profi...
[5] https://www.invesco.com/qqq-etf/en/about.html