In general, this meta post would have an objective answer of "yes" or "no" with simple reasoning; however, I have added "(but what if)" because I am looking for additional answers in case of not-so-simple reasonings.
Can I award a bounty to an answer that I like, which was asked in 2017, has received an answer that says, "You can absolutely do that"--in short, yes.
Following that, I wanted to clarify this matter: What if the answer that I like seems underappreciated, but is not accepted and having mixed votes or zero votes?
Example post: What does it mean to make a bootable LiveUSB?
Recently (see timeline), I have started my first bounty on the example post. The question itself somehow received a mixed response until the post has been revised by OP about four months ago. I consider this question is very relevant to anyone whom just about to try using Ubuntu, then soon discovered that creating Live USB is not the same as Live CD, as in copying (writing) ISO file to the storage media.
In the example post, the most voted answer (also the longest answer) has been accepted as the best answer by OP. Personally, I do not think that is the best answer at all. There are several other answers that use less words but does a better job at answering the question.
So I started a bounty to bring attention to the post and to appreciate the answer that I like. But what if I decided to award bounty to either one of these:
Case A (mixed votes): This answer by sudodus has total votes of +5/-1, but not sure why the -1 vote. Down-vote reason is not known. At least one commentator appreciated this answer.
Case B (zero votes): This answer by Dmitry Grigoryev has total votes of +1/0, but I consider that as having zero votes because +1 was voted by myself. Am I the only one who think this is also a good answer?
Note: If necessary, I will post a meta answer below to explain my reasoning why both answers are good, despite each has a different approach.
My concern is that the non-accepted answers that I like seem to have relatively less votes or zero votes. So far, I do not recall any bounty being awarded to such posts on Ask Ubuntu (and not even other Stack Exchange sites that I had joined so far).
In other words, bounties are usually awarded to either: Accepted answer, or most voted answer, or least voted but the only answer.
Hence my meta question: Say I decided to award a bounty to such answer. As a result, will my decision cause the awarded answer to be targeted by unexpected down-votes or disagreement by the community? What are the recommended steps to appreciate such answer without causing such unintended result?
TL;DR: Started a bounty to appreciate the underappreciated answers, but now I chickened out, thinking of possible disagreement and such unintended result due to awarding bounty to least voted answers.