that suggestion isn't even viable on Tor websites
At work I run a hardened browser that disables a hell of a lot more than JS and not only do most pages work just fine as far as providing the content I wanted from them, but they load faster and look cleaner. There are still some annoying cases when a website can't even manage to display text or images without JS enabled, but even as easy as it is to enable JS if a website is that broken I often just close that tab and move on with my life anyway. I don't use that browser for things like online shopping but for 90% of what I need it works while also being far better for security and privacy
A surprising number of sites work, at least well enough, with JS disabled. When they don't I can selectively enable JS as needed until I get the functionality required. Often that is a single permission or two, while I keep everything else disabled.
If you're willing to dedicate the troubleshooting time to your web experience you can get yourself into a pretty useable state over time though.
i use uBlockOrigin for ad block. it have a setting "disable js". done.
each site you visit either works... or you leave it. if you must use it and it's a blank page, press ctrl+e, or open the ad blocker UI (works even on Firefox Android) and uncheck the blocked js icon. again, done. two clicks or one keyboard shortcut.
and as the comment your replying to said, you will be surprised how everything works fine without
Also if you just whitelist every site the instant they don't work it's not exactly a security gain. Maybe it helps with ads UBO isn't catching out of the box or some other angle though. The amount of security you gain from this is proportional to the amount of effort you're willing to invest in making sites work. As an example: https://news.ycombinator.com/item?id=40069834 site works fine without one day, then suddenly doesn't so you whitelist or futz around until you find something like the /embed trick, until that either changes some day too or you've given up and just whitelisted every site you go to anyways.
you seen to spend time here, so you'd pay the security price and that's it.
not having js on by default is for the 95pct of domains you hit everyday to read a single paragraph and never return.