To lift the kimono:
It's often easier to search within a specific timeframe on Hacker News itself given Algolia search's excellent date-range functions, and the fact that HN itself is strongly time-oriented. There are doubtless other stories elsewhere, but it would be more tedious to track those down and verify that they actually came from the period under consideration.
It's also possible to search via comments, with one useful set of terms being "Google+" and "ghost town", an assessment which was being thrown about early on.
And we can link directly to the HN threads and see what contemporaneous discussions were like and how they characterised the issue at the time.
By contrast, date-ranged General Web Search on, say, DuckDuckGo or Google is often confounded by Web pages which have inaccurate date indicia, or have been misclassified as to time by search engines. It's much more tedious to try to find specific content matching time criteria, though the universe of total such articles is obviously larger. Fortunately for this case, Google+ was of sufficient interest to HN that there were numerous submissions concerning it submitted early on, many of course highly syncophantic, but also concerning the rather fumbling rollout and weak adoption.
Amongst other possible archives, Google+ itself is no longer extant, and so cannot be searched. Its own search features did not afford date-ranged search, though I'm well aware that there was much early hand-wringing over the "brutally unfair" stories (in the framing of G+ advocates) circulating at the time.
Reddit might be another useful trove, though I'm avoiding that for the time being. Search there is limited to only the initial story title and, in a limited number of cases, the "self-text" content of text-based posts. Pointedly, comments aren't searchable on Reddit itself, and so the potential match space is far more constrained than it is on Hacker News.
Despite those limitations, in answering your own historically uninformed vague hand wave that the response to Facebook's Threads launch is exceptional, I'd given numerous specific and quantified examples from a roughly comparable time period for Google's G+ launch strongly suggesting otherwise.
Yes, the data I brought to bear are subject to a strong availability heuristic. But the evidence presented is rather stronger than your own none-at-all offerings.
Cheers.