Has anyone DCA into ETFs for 20 years already? What's your returns like?

The total 20 year performance of individual portfolios is very difficult to calculate for retail investors, because of sometimes aperiodic investments or cash outs. there are various methods (XIRR etc.). I feel to answer your question you'll get a hint when you look into the ETFs fact sheet-pdfs all available on the internet and look into the 10 year performance % numbers (20 year numbers are not available).

For have some hints for ETFs as old as 20 years you could use Bigchart's tool, as here SP500 compared to QQQ ETF:

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