I’ve posted answers on many sites for decades
In all fairness, Stack Exchange sites (of which Ask Ubuntu is one) are not like other sites. If you've been participating in online communities for that long, I'm sure you can agree that it's best to follow the guidelines of each community you participate in.
this was my first answer on this site although I’ve used [it] for years
If you've been reading here for years, then please consider that you've already benefited greatly from these very guidelines that make the site what it is!
The moderator indicated I asked a question didn’t provide an answer
Well no, the Mod indicated that you had a comment rather than an answer. And while you may believe you provided an "answer", you really didn't according to the guidelines of the site.
It's important to realize that Ask Ubuntu is not a "discussion site" or forum. It's a question-and-answer site, with a specific set of guidelines in place to help it succeed in that purpose.
In light of the community guidelines, your answer reminds me of a quote from Isaac Asimov's Foundation:
“The analysis was the most difficult of the three by all odds. When Holk, after two days of steady work, succeeded in eliminating meaningless statements, vague gibberish, useless qualifications - in short, all the goo and dribble - he found he had nothing left. Everything cancelled out.
Lord Dorwin, gentlemen, in five days of discussion didn't say one damned thing, and said it so you never noticed.”
Not that your post is "vague gibberish", but doing an "analysis" against it, there's mainly:
"I ... am experiencing a general sluggishness as well."
This makes it sound like you are currently having the same problem, rather than having solved it (even partially) and providing an answer. Substituting the word "am" with "was" would help set the stage for an answer.
"Horrible keyboard / can't enter a password / Video still lags / Likely not the root cause of the sluggishness / if I can't get it stable I can always reinstall 20.04 / many of the UI utils appear to be not quite there yet / still appears rather rough / so yeah, bleeding edge"
Perhaps this isn't "vague gibberish", but it definitely doesn't help to provide an understanding the issue or the solution. Honestly, it just comes across as "ranting". It's absolutely okay to point out that there are quality issues, but that shouldn't take up 80% of your post.
In general, Stack Exchange sites have an "anti-fluff" policy. The answer should focus on the solution, rather than recapping your problems.
"I made a few tweaks and this helped but still slow."
But you don't list any tweaks that you made in that section, and based on the "still slow", we assume you're still having the issue. If the tweaks helped, though, then it would be better to include them in the answer.
"I was able to expand, which helped but not a lot."
But there doesn't seem to be any indication in the original question that the OP ran out of space. As such, this is extraneous information that isn't useful to answering the question; just describing one of your issues and how you resolved it.
"I did find one article that mentioned changing the disk cache to a memory cache. I did this and helped a lot."
That's great, but please understand that linking to a website is still considered "Not an Answer" here unless you also include at least a summary of the steps necessary to fix it. See the Why and how are some answers deleted? Help:
barely more than a link to an external site (i.e. the actual answer is not included in the post)
So as with Asimov's semantic analysis, once we cancel out the "fluff" and rants, we're left with a link only answer, which also gets cancelled out.
Perhaps so, although I hope not. You say that you've been a reader here for years, so again, these guidelines that you ran afoul of have worked to create a site that you've enjoyed from the other end. Hopefully, you can work within these guidelines in answering questions in the future.
As @ArturMeinild said, your post could certainly be edited into a reasonable answer that might help some readers make progress on related issues, if you have the desire to do so.