My beginning "investment" (mining/time) in bitcoin hit 9 years a week or two ago - July 11, 2010 after the Slashdot story on it.  It certainly has done well for 9 years, if the next 10 are even 1% as good as the previous 9, everyone who has some bitcoin will be quite happy.

An ETF to help ease of entry for more people (e.g. in retirement accounts, brokerages etc) will go a long way to helping people purchase bitcoin and take part in any future gains.