You cannot think about 'The Lord of the Rings' without Hobbits coming to mind.
This is most likely why the producers of the new original series 'The Rings of Power' included the Harfoots, as a nod to some of Middle-Earth's most prominent people. However, the roaming Harfoots as depicted on the show do not quite meet the familiarity of the Hobbits we are used to. A number of fans have been questioning the depiction of characters in the show, in comparison to the descriptions from Tolkien's novels. The inclusion of black actors for the Harfoots, in particular, has viewers genuinely asking, 'Are there black hobbits in Middle-Earth'?
The Rings of Power is an entirely new story based upon the works of Tolkien, set an age before the events of the novels. The Harfoots are one of three breeds of Hobbit. And within the setting of the show, a very early depiction of them. This halfling community is therefore the ancestors who would become the settlers of The Shire. Including the Hobbits, we recognise such as Bilbo and Frodo Baggins, Samwise, Merry, and Pippin.
Considering these are relatives of, but not directly the same race which is featured within Tolkien's books, it is not entirely unimaginable to conceive that black Hobbits (or a Hobbit of any skin color) could exist within the realms of Middle-Earth. However, some 'Tolkien experts' state that their existence within the Westlands during this period is not very likely if you accept the lore as accurate. They also cast doubt that there could be any form of Hobbit this fast west of Middle-Earth at all, considering the written origin of their heritage.
Of course, not everyone agrees with the exact characterization of Harfoots either. The prolific and respected writer Neil Gaiman, who has produced many fan-loved novels of his own, provided his alternative opinion on the matter. The author of such works including American Gods, Stardust, Good Omens, and Sandman (all of which have been made into their own on-screen adaptations), stated on Twitter that
"Tolkien described the Harfoots as 'browner of skin' than the other hobbits. So I think anyone grumbling is either racist or hasn't read their Tolkien. Your mileage may vary".
Evidently, assessing the mythology of Middle-Earth as composed by Tolkien, is not an obvious guide to answering concerns of Harfoot ideology.
What can be considered canon
One issue which complicates the comparison between the portrayal of The Rings of Power and Middle-Earth lore is the limitations of which source material can be used and which cannot. Much of the descriptions of early Middle-Earth and Hobbit history come from Tolkien's other works, which are separate from the main novels he is most known for. Tolkien wrote little of the importance of Hobbits outside the Third Age; which is the period in which both 'The Hobbit' and 'The Lord of the Rings' are set.
One such publication is 'The Book of Lost Tales', which was written much later and not published until the early 1980s. However, the limited knowledge these tales do provide concerning the Harfoots cannot be used by the series at all. This is because Amazon only purchased the rights to Tolkien's predominant books, and can therefore only base the show on details contained strictly within those novels, and nothing else.
If all of Tolkien's works combined create the canon for the Lord of the Rings universe, surely anything which omits certain details from its entirety cannot be considered accurate canon. The Rings of Power may include characters and recognisable features of the Tolkien universe, but it is an original interpretation at most. Although this means it cannot be likely classed as canon, it can interpret details of Middle-Earth and its people as it chooses. And by that measure, Hobbits or Harfoots of any ethnicity can appear all the same. It may not be Tolkien's Middle-Earth, but it's still Middle-Earth all the same.