Same experience over here. Other search engines do have Typewriter Talk at the top of their "typewriter forum" search results. But on Google the forum seems to be non-existent.
Google shows only hits in relation to Typewriter Talk if other web pages are mentioning this forum.
Examples:
https://site.xavier.edu/polt/typewriters/tw-lists.html
https://filthyplaten.com/2015/07/02/a-quick-review-of-online-typewriter-communities/

Could it be the case that Google's web crawling robots are blocked by the forum's software?

Let's try to get an answer from Google via it's artificial intelligence chatbot Gemini.

Q:
Do you know the 'Typewriter Talk' internet forum? Why does the Google search for 'typewriter forum' have no direct results for this search phrase in relation to the 'Typewriter Talk' internet forum?

A:
>>> It's true that searching for "typewriter forum" can yield a variety of results, and pinpointing a specific forum like "Typewriter Talk" can sometimes be tricky. Here's a breakdown of why this might occur:

• Search Engine Algorithms:


• Google's algorithms prioritize relevance, popularity, and other factors. General terms like "typewriter forum" might bring up broader results, such as popular Reddit threads (r/typewriters), general typewriter community websites, or large databases.
• Older forums or those with less frequent updates might rank lower in search results.
• Varied Online Presence:
 The "typewriter community" exists in various forms: forums, social media groups, blogs, and email lists. This fragmented presence can make it difficult for a single forum to dominate search results.  
 Some online communities, especially older ones, may not have the same level of SEO (Search Engine Optimization) as newer platforms.

Community Structure:
  "Typewriter Talk," like many niche forums, might rely on word-of-mouth and direct links within the community, rather than heavy reliance on search engine traffic.
  Also some older forums can have older web technology that is not as well indexed by modern search engines.

•  
• General Search Terms:


• When a general search term like "typewriter forum" is used, search engines will return the most popular and broadly used websites. So sites like reddit, and sites that have large databases of typewriter information will likely be returned.


• Here are some points to consider regarding the typewriter community online:
• The typewriter community is very active online, but it is spread across different platforms.Resources like "The Typewriter Database" and blogs like "The Typewritemosphere" are very valuable resources.
Reddit's r/typewriters is a very active community.

I hope this information is helpful.<<<


I personally think that the technical reasons given by Gemini that are the most logical ones:

Some online communities, especially older ones, may not have the same level of SEO (Search Engine Optimization) as newer platforms.
Also some older forums can have older web technology that is not as well indexed by modern search engines.

and this:

When a general search term like "typewriter forum" is used, search engines will return the most popular and broadly used websites. So sites like reddit, and sites that have large databases of typewriter information will likely be returned.

On the other hand the large number of registered forum users (18,837) speaks definitely for some kind of presence.
 

Eagle wrote:

Let's try to get an answer from Google via it's artificial intelligence chatbot Gemini.

I decided to do the same thing and my result was:

Gemini (and almost certainly Google) thinks the Typewriter Talk forum no longer exists because it believes Boardhost shut down sometime in 2024 (I believe I first noticed this issue early last year).  I argued with Gemini repeatedly that this was incorrect, insisting I was on the site at that moment, was logged in, and just commented, but it still didn't believe me. Gemini did not relent until I told it that the Typewriter Talk forum is the number one result in Bing, Yahoo, DuckDuckGo, and Qwant, at which point I think it decided to search via those engines and finally apologized to me for being wrong.  After telling me I was right, it said it was most likely a technical issue with the forum's configuration (this might mean Boardhost) that is preventing Google from indexing it properly.

For over a year now, this site has been completely invisible to Google. Not a lower ranking, but the entire content of this forum is completely gone.  This is a huge problem because about ~90% of search traffic goes through Google. In addition to previously being the top search result in Google for 'Typewriter Forum', Typewriter Talk was often the top result for typewriter questions. Currently, the only people who will be able to find this forum, and its dozen years of typewriter discussions, would have to pretty much arrive via a bookmark, link, full address in their browser, or be among of the ~10% that doesn't use Google for search.

Of the fixes the Gemini recommended, the first one seemed to be the only applicable one considering this is not an issue with other search engines. It reads as follows, and I am not sure if it is referring to Type Talk, or to Boardhost when it says 'forum owner':

Actions the Typewriter Talk forum owners can take:  Since the forum is already active on other search engines, it's not a technical issue with the website being down, but rather an issue with how Google is indexing it. The forum's administrators can focus on the following steps to improve its standing with Google:

1.    Use Google Search Console. The most important tool is Google Search Console. The forum's administrator should:
           - Submit a sitemap: A sitemap file lists all the important URLs on a website, which can help Google's crawlers find pages they might otherwise miss.
           - Request indexing: The admin can manually submit the URL for the forum's index page, and other important pages, through the URL Inspection tool to ask Google to crawl them.
           - Check for indexing issues: Search Console can identify specific problems that are preventing pages from being indexed, such as a misconfigured robots.txt file or "noindex" tags that accidentally block Google.