theyre both given the ability of teleportation(but i feel obito is the only one able to become intangible and ill explain why). kakashis is just through eyesight and purely for attack because everything that gets warped gets ripped or torn to shreds like a chunk is being taken out. Kakashis eye also being long range is a misconception, its just through his eye and whatevers in his line of sight gets kamui'd. Obitos on the other hand is through contact, therefore any part of obitos body is able to "warp" and become intangible because its all connected to his eye through contact. Thats why its almost second nature to him, because it all happens through contact. Kakashi cant send kamui things with with touch alone while obito cant kamui with his eyes. And think about the potential if he had both... Theoretically, obito would be able to make himself intangible while making his attacks tangible (ie. katon would travel from the kamui dimension to the real world via kakashis sharingan, while obito uses eye his to become intangible)
P.S. kakashis kamui has the opposite effect on people as obitos, so taking that into account, kakashi can warp people away from far distances (slowly) and warps himself fast. while obito warps himself himself slowly and people fast.