The other day, Google employee John Muller disproved the idea that the search engine may remember the page that previosly contained the noindex directive.
Some experts believe that Google remembers this information and continues to take it into account even after the removal of the corresponding directive. As a result, this may make it difficult to re-index the page in the future.
However, Mueller assured that this is not so.
NIX Solutions reminds that in September 2019, Google stopped supporting the noindex directive in the robots.txt file.