It's useful from my point of view to look for some Arthurian links as I can see some there myself and have done since I first read any Tolkien - how many British kids went through early childhood without absorbing some of the Arthurian myths? It might even be inevitable for a British reader to draw these parallels at some point.
But I also think that these kinds of parallels are pretty central to that something 'indefinable' about Tolkien's work, that sense that it's somehow 'real', and they have a lot to do with his aim to dedicate a mythology for England (note,
not to create a new one!). The more I look, the more I see the deep layers of British archaeology, history, and of folklore and mythology (as fragmented as these are), all wrapped up in living language which has genuine meaning. Does that make sense? It's something I'm mentally working out and have been for some time.

Basically, all the layers of our known folklore and ancient history, even the layers of our landscape are to be found woven into Tolkien's stories, including Arthur, Robin Hood, the Celtic, Roman, Saxon and Norse gods, the mysteries of the ancients....
So to Arthur. Even at the surface level there's so much to see that links Aragorn with Arthur. Boys brought up in foster homes, who inherit/earn magical swords, the 'fairy wife' they both earn, the need to prove their kingship, the quasi-holy drive. The biggest comparison is a big one though. Both of these kings are intended, destined to be kings who reunite fragmented kingdoms. This is even borne out in historic knowledge of who Arthur may have been as he is linked to both the kingdoms of the South West and to the kingdoms of the North, and Aragorn too is a link between North and South. they are long-hoped for Kings, ideal Kings, genuinely mythical Kings.
And this is without even considering the Gandalf-Merlin possibilities or who Galadriel may be (Lady of the lake or Morgan le Fay?). Or other linguistic connections such as Avalon/Avallone. And there's more.
The point is that none of these characters 'equal' characters from real myths and folklore, but they resonate with those older tales and contribute to this layered re-interpretation of Britain.