When I was in middle school (1980s) we did a tax return on paper, I think it was part of a Social Studies class? We were given a fictitious W2, number of dependents, etc. and had to fill out a 1040 and a State return (on paper of course, no computers then). This permanently demystified the process. I think a lot of people who pay HRBlock or similar to do their taxes have never tried to do their taxes manually and are just afraid to try.

I have always done my taxes myself, on paper, even years when I had capital gains, education credits, 1099s, and small business (single member LLC) income. It's a bit time consuming but not difficult per se.

I believe that's only for filing a federal tax return, and for filing your state tax return you still have to either use a tax preparation website or do it on paper.

California has a had a wizard-style site for... I'm not sure a decade or so.

Here:

https://www.ftb.ca.gov/file/ways-to-file/online/index.html

Maybe a bit of an open secret? Found with "site:ca.gov", halfway down the DDG page.

Other little-known, useful USA services:

weather.gov new.nowcoast.noaa.gov

Many states offer online filing systems, might even be the majority now. You just have to visit the state’s tax department website.