2010: wind+solar just aren't powerful enough technologies to scale to the problem.
2012: wind+solar are fine, but too dependent on subsidies.
2016: wind+solar are now too cheap, and it's messing up powergrid economics.
2019: let's rip out the old, and replace w/ wind+solar. pic.twitter.com/CzRAEabzcB

— Gregor Macdonald (@GregorMacdonald) October 12, 2019

Also, forgotten:

1970: These crazy hippies think they can make power from the air and sun. Ha!

1980: We have solar-powered calculators now. That’s all it will ever be useful for.

1990: Solar power might be used someday for really low-power applications, but nothing else. Wind is pointless altogether.

1998: Wind and solar is way, way, way, too expensive to use for anything ever, and if you say anything else, you are crazy and banned!