If true, this would be big news, as the "+" qualifier on search terms stopped being obeyed about a decade ago with the launch of... whatever that now-forgotten Facebook competitor Google used to have. The workaround was to use quotes around individual words, which mostly worked, unless it didn't. But the combination of using quotes and "verbatim" (under Tools/All Results") almost always worked.
[1] The way it failed is sort of interesting. I randomly tried "+rhino +cereal +gm", and the first result didn't include the word "rhino", and considered "gm" to be a synonym for General Mills. Quotes around the individual terms seems to work for this query, even without verbatim.
Based on Google’s advanced operator page at one point, the addition of a plus sign to a search termed either prompted the lookup of Google+ pages or a blood type.
'+' was replaced by adding quotes around each search term.
[0] https://googlesystem.blogspot.com/2011/10/googles-plus-opera...