
ehhhhh half true. Lee was a B+ tactician and was very talented at Napoleonic warfare, which was becoming irrelevant due to rifle accuracy over long distances improving. Grant had the intelligence to fully use the Union’s advantages in numbers and took advantage of new technology. Obviously Lee and his cause were repugnant, which is a different conversation entirely.
Grant also had a few moments of brilliance, like Vicksburg and Shiloh. Grant in Virginia was messy, which I understand was intentional and was a strategically competent move, but Grant deserves more credit for his courage and determination to make correct but unpopular calls, rather than tactical genius.
I can appreciate Lee's tactical capability, but I have a hard time crediting much to it. I have to balance it against Lee's and the rest of the confederate army's overall strategic failure: the choice to fight a largely open war against a foe far better suited to it. Tactical prowess means little when your whole approach is flawed.
I do think you've correctly assessed Grant. He was far plainer than Lee, which I believe leads people to underestimate him. But as you say, he adapted well to the Army he had and the tech of the time, and was willing to make tough choices in the pursuit of the overall goal. I think his ability to see those choices through is what allowed him to eventually win- it's so funny because he's like the inverse of McClellan lol