This is not a replacement for searching for a specific string in `less` which highlights the matches, and eliminates the need for scanning the text manually which is harder and prone to missing information.
Correct, however the author is saying that there's no reason to ever use tail unless you're tailing multiple files, which is false. Most of the functionality you want is already built into your terminal emulator. If you want slower updates (`less` uses 1 second polling, vs `tail` [inotify]), and the ability to search, by all means, use `less`.