I am an engineer on Google Search frontend.
Thank you for posting this, and I'm really sorry and saddened to see this broken; this is certainly not intended behavior.
I've reproduced the issue you described in the blog (Lynx does not allow clicking on the search results page). Even though Google serves valid HTML to Lynx, it's probably HTML that Lynx cannot parse, and since it used to work before, this is a regression. I filed a bug for our team to look further into it and address the root cause.
Interestingly enough, pressing <L> shows a list of links in the current document, and it does show all the available result links, so Lynx does see and parse them, it's just not rendering the links inline with the search results, so that's something we have to investigate as well.
In the meantime, as a temporary workaround, if you're open to using Chrome with a simple UI that would be amenable to a screenreader and keyboard navigation, you can use a User Agent switcher extension by Google [1] to set the user agent header to Lynx [2] and Google will serve the same HTML that it would have served to Lynx. You can then use the <Tab> key to iterate over the search results, and <Enter> to select a particular result.
I look forward to seeing this bug resolved, and will be personally following up on the status of this bug.
Again, I'm really sorry to see this, and I hope we'll be able to restore your ability to use Google with Lynx shortly!
[1] https://chrome.google.com/webstore/detail/user-agent-switche...
[2] https://developers.whatismybrowser.com/useragents/explore/so...