Should is an interesting term, but in any case the concept behind name-spaces is to avoid clashing.
In the days of C and other languages like it :-) , you had functions. If two libraries provided the same function name, you could be out of luck at either compile or link time.
/* code dealing with gui */
/* code dealing with printer */
So we started to get in the habit of adding a little company/library based prefix
Library Other one:
/* code dealing with GUI */
Library Other two:
/* other print code */
And this helped quite a bit, more typing, but since you were less likely to use two of the same library in the same application, it did pretty well.
Languages evolved and the concept became more refined to be a first class concept of namespaces.
Java (citation needed) may have been the first to (widely) adopt the reversed domain name as a namespace. By the very nature of the DNS system, this ensured that there would be no clashing of same names.
So back to should; if you are coding for your personal use, then likely don't bother worrying about it.
If you are coding for a company, consider using their name in the standard reverse order. If the code does not go anywhere else (i.e. is not released open-source), it will not make much of a difference, but it will be least surprise item for future developers who come along and expect that standard convention.