A president that was firm in their convictions and got things done. Sounds nice. While the landscape was completely different in American politics at the time, it's still hard to not revere somebody that could actually get important decisions to happen instead of the endless dribble of nothingness we get today. Far from perfect, but still preferable to this mess.
Lincoln is revered because he managed to keep the nation together at at time when that seemed impossible. He wasn't a perfect president or a perfect man but he used his circumstances to do the best he could and what he achieved was actually amazing. So revering him makes sense, especially during a time when we feel so deeply divided.
I personally had no problem with Abraham Lincoln being reserved and laid back. I actually like when people who are in positions of power are calm, cool, and collected. It let's me know that they will be able to handle stressful situations well. Lincoln might now have been very animated but he was one of the best presidents ever.
I think Lincoln did an okay job a being president, but history books and the media definitely paint a very different picture of him. Lincoln wasn't particularly very interested in equal rights for African slaves, he only used that as leverage to push his idea that the states should be unified. I think his persona is more based on Young Mister Lincoln and all of the iconography that we're surrounded by that glorify him.